path: root/doc/ProofGeneral.texi

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@c
@c $Id$
@c
@c NB: the first line of this file uses a non-standard TeXinfo
@c hack to print in Serifa fonts.  It has no effect if you don't have
@c my hacked version of TeXinfo - da.
@c
@c 
@setfilename ProofGeneral.info
@settitle Proof General
@setchapternewpage odd
@paragraphindent 0
@c A flag for whether to include the front image in the
@c DVI file.  You can download the front image from
@c http://www.proofgeneral.org/ProofGeneralPortrait.eps.gz
@c then put it into this directory and 'make dvi' (pdf,ps)
@c will set the flag below automatically.
@clear haveeps
@iftex
@afourpaper
@end iftex

@c
@c Some URLs.
@c FIXME: unfortunately, broken in buggy pdftexinfo.
@c so removed for now.
@set URLxsymbol  http://x-symbol.sourceforge.net
@set URLisamode  http://www.proofgeneral.org/~isamode
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@set URLpglatesttar  http://www.proofgeneral.org/ProofGeneral-latest.tar.gz
@set URLpglatestdev  http://www.proofgeneral.org/ProofGeneral-devel-latest.tar.gz
@c
@c

@c
@c IMPORTANT NOTES ABOUT THIS TEXINFO FILE:
@c I've tried keep full node lines *out* of this file because Emacs makes a
@c mess of updating them and they are a nuisance to do by hand.  
@c Instead, rely on makeinfo and friends to do the equivalent job.  
@c For this to work, we must follow each node
@c immediately with a section command, i.e.:
@c
@c  @node node-name
@c  <section-command>
@c
@c And each section with lower levels must have a menu command in
@c it.  Menu updating with Emacs is a bit better than node updating,
@c but tends to delete the first section of the file in XEmacs!
@c (it's better in GNU Emacs at the time of writing).
@c
@c LINE BREAKS: For html generated from this to look good, it is
@c important that there are lots of line breaks/blank lines, esp
@c after @enddefn's and similar.  Otherwise text flows on the same
@c paragraph but gets coloured wrongly with Netscape's handling of 
@c style sheets.
@c
@c reminder about references: 
@c        @xref{node}  blah         start of sentence: See [ref]
@c        blah (@pxref{node}) blah  bla (see [ref]), best at end of sentence
@c        @ref{node}                without "see". Careful for info.
@c

@set version 3.4
@set xemacsversion 21.4
@set fsfversion 21.2
@set last-update July 2002
@set rcsid $Id$

@ifinfo
@format
START-INFO-DIR-ENTRY 
* Proof General: (ProofGeneral). Organize your proofs with Emacs!  
END-INFO-DIR-ENTRY
@end format
@end ifinfo

@c
@c MACROS
@c
@c define one here for a command with a key-binding?
@c
@c I like the idea, but it's maybe against the TeXinfo
@c style to fix together a command and its key-binding.
@c
@c merge functions and variables into concept index.
@c @syncodeindex fn cp
@c @syncodeindex vr cp

@c merge functions into variables index
@c @syncodeindex fn vr

@finalout
@titlepage
@title Proof General
@subtitle Organize your proofs!
@sp 1
@subtitle User Manual for Proof General @value{version}
@subtitle @value{last-update}
@subtitle @b{www.proofgeneral.org}

@c nested ifs fail here completely, WHY?
@iftex
@ifset haveeps
@c @vskip 1cm
@c The .eps file takes 8.4M!  A pity texi can't seem
@c to deal with gzipped files? (goes down to 1.7M).
@c But this still seems too much to put into the
@c PG distribution just for an image on the manual page,
@c so we take it out for now.
@c Ideally would like some way of generating eps from
@c the .jpg file.   
@c image{ProofGeneralPortrait}
@end ifset
@end iftex
@author David Aspinall with P. Courtieu, H. Goguen, T. Kleymann, D. Sequeira, M. Wenzel.
@page
@vskip 0pt plus 1filll
This manual and the program Proof General are
Copyright @copyright{} 1998-2002 Proof General team, LFCS Edinburgh.

@c
@c COPYING NOTICE
@c
@ignore
Permission is granted to process this file through TeX and print the
results, provided the printed document carries copying permission notice
identical to this one except for the removal of this paragraph (this
paragraph not being relevant to the printed manual).
@end ignore

@sp 2
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.  
@sp 2

This manual documents Proof General, Version @value{version}, for use
with XEmacs @value{xemacsversion} and GNU Emacs @value{fsfversion} or
later versions.  Proof General is distributed under the terms of the GNU
General Public License (GPL); please check the accompanying file
@file{COPYING} for more details.

@sp 1

Visit Proof General on the web at @code{http://www.proofgeneral.org}

@sp 1

@code{@value{rcsid}}
@end titlepage

@page


@ifinfo
@node Top
@top Proof General

This file documents version @value{version} of @b{Proof General}, a
generic Emacs interface for proof assistants.

Proof General @value{version} has been tested with XEmacs
@value{xemacsversion} and GNU Emacs @value{fsfversion}.  It is
supplied ready customized for the proof assistants PhoX, Coq, Lego, 
Isabelle, and HOL.  

@menu
* Preface::                     
* Introducing Proof General::   
* Basic Script Management::     
* Proof by Pointing::
* Advanced Script Management::  
* Support for other Packages::  
* Hints and Tips::
* Customizing Proof General::   
* LEGO Proof General::          
* Coq Proof General::           
* Isabelle Proof General::    
* HOL Proof General::
@c * PhoX Proof General::
* Obtaining and Installing::  
* Known bugs and workarounds::  
* References::                  
* Function Index::              
* Variable Index::              
* Keystroke Index::             
* Concept Index::               
@end menu
@end ifinfo

@node Preface
@unnumbered Preface

Welcome to Proof General!

This preface has some news about the current release series, as well as
some history about previous releases, and acknowledgements to those who
have helped along the way.

Proof General has a home page at
@uref{http://www.proofgeneral.org}.  
Visit this page for the latest version of this manual,
other documentation, system downloads, etc.


@menu
* Latest news for 3.4::
* Future::
* Old News for 3.3::
* Old News for 3.2::
* Old News for 3.1::
* Old News for 3.0::
* History before 3.0::                     
* Credits::                     
@end menu

@node Latest news for 3.4
@unnumberedsec Latest news for 3.4
@cindex news

Proof General 3.4 adds improvements and also compatibility fixes for
new versions of Emacs, in particular, for GNU Emacs 21, which adds
most of the pretty features that have only been available to XEmacs
users until now (toolbar and X-Symbol support).

One major improvement has been to provide better support for
synchronization with Coq proof scripts; now Coq Proof General should
be able to retract and replay most Coq proof scripts reliably.  Credit
is due to Pierre Courtieu, who also updated the documentation in this
manual.

As of version 3.4, Proof General is distributed under the GNU General
Public License (GPL).

See the @file{CHANGES} file in the distribution for more complete
details of changes since 3.3.


@node Future
@unnumberedsec Future
@cindex Proof General Kit
@cindex Future

The aim of the Proof General project is to provide a powerful and
configurable interfaces which help user-interaction with interactive
proof assistants.  

The strategy Proof General uses is to targets power users rather than
novices; other interfaces have often neglected this class of users.  But
we do include general user interface niceties, such as toolbar and
menus, which make use easier for all.

Proof General has been Emacs based so far, but plans are afoot to
liberate it from the points and parentheses of Emacs Lisp.  The
successor project Proof General Kit proposes that proof assistants use a
@i{standard} XML-based protocol for interactive proof, dubbed @b{PGIP}.

PGIP will enable middleware for interactive proof tools and interface
components.  Rather than configuring Proof General for your proof
assistant, you will need to configure your proof assistant to understand
PGIP.  There is a similarity however; the design of PGIP was based
heavily on the Emacs Proof General framework.

At the moment little work has been done: collaborations are eagerly
sought.  For more details, see @uref{http://www.proofgeneral.org/kit,
the Proof General Kit webpage}.



@node Old News for 3.3
@unnumberedsec Old News for 3.3

Proof General 3.3 includes a few feature additions, but mainly the focus
has been on compatibility improvements for new versions of provers (in
particular, Coq 7), and new versions of emacs (in particular, XEmacs
21.4).

One new feature is control over visibility of completed proofs,
@xref{Visibility of completed proofs}.  Another new feature is the
tracking of theorem dependencies inside Isabelle.  A context-sensitive
menu (right-button on proof scripts) provides facility for browsing the
ancestors and child theorems of a theorem, and highlighting them.  The
idea of this feature is that it can help you untangle and rearrange big
proof scripts, by seeing which parts are interdependent.  The implementation
is provisional and not documented yet in the body of this manual.  It only
works for the "classic" version of Isabelle99-2.

See the @file{CHANGES} file in the distribution for more complete
details of changes since 3.2.




@node Old News for 3.2
@unnumberedsec Old News for 3.2
@cindex news

Proof General 3.2 introduced several new features and some bug fixes.
One noticeable new feature is the addition of a prover-specific menu for
each of the supported provers.  This menu has a ``favourites'' feature
that you can use to easily define new functions.  Please contribute
other useful functions (or suggestions) for things you
would like to appear on these menus.

Because of the new menus and to make room for more commands, we have
made a new key map for prover specific functions.  These now all begin
with @kbd{C-c C-a}.  This has changed a few key bindings slightly.

Another new feature is the addition of prover-specific completion
tables, to encourage the use of Emacs's completion facility, using
@kbd{C-RET}.  @xref{Support for completion}, for full details.

A less obvious new feature is support for turning the proof assistant
output on and off internally, to improve efficiency when processing
large scripts.  This means that more of your CPU cycles can be spent on
proving theorems.

Adapting for new proof assistants continues to be made more flexible,
and easier in several places.  This has been motivated by adding
experimental support for some new systems.  One new system which had
good support added in a very short space of time is @b{PhoX} (see
@uref{http://www.lama.univ-savoie.fr/~RAFFALLI/af2.html, the PhoX home
page} for more information).  PhoX joins the rank of officially
supported Proof General instances, thanks to its developer Christophe
Raffalli.

Breaking the manual into two pieces was overdue: now all details on
adapting Proof General, and notes on its internals, are in the
@i{Adapting Proof General} manual.  You should find a copy of that
second manual close to wherever you found this one; consult the
Proof General home page if in doubt.

The internal code of Proof General has been significantly overhauled for
this version, which should make it more robust and readable.  The
generic code has an improved file structure, and there is support for
automatic generation of autoload functions.  There is also a new
mechanism for defining prover-specific customization and instantiation
settings which fits better with the customize library.  These settings
are named in the form @code{@i{PA}-setting-name} in the documentation;
you replace @i{PA} by the symbol for the proof assistant you are
interested in.  @xref{Customizing Proof General}, for details.

Finally, important bug fixes include the robustification against
@code{write-file} (@kbd{C-x C-w}), @code{revert-buffer}, and friends.
These are rather devious functions to use during script management, but
Proof General now tries to do the right thing if you're deviant enough
to try them out!

Work on this release was undertaken by David Aspinall between
May-September 2000, and includes contributions from Markus Wenzel,
Pierre Courtieu, and Christophe Raffalli.  Markus added some Isar
documentation to this manual.


@node Old News for 3.1
@unnumberedsec Old News for 3.1
@cindex news

Proof General 3.1 (released March 2000) is a bug-fix improvement over
version 3.0.  There are some minor cosmetic improvements, but large
changes have been held back to ensure stability.  This release solves a
few minor problems which came to light since the final testing stages
for 3.0.  It also solves some compatibility problems, so now it works
with various versions of Emacs which we hadn't tested with before
(non-mule GNU Emacs, certain Japanese Emacs versions).

We're also pleased to announce HOL Proof General, a new instance of
Proof General for HOL98.  This is supplied as a "technology
demonstration" for HOL users in the hope that somebody from the HOL
community will volunteer to adopt it and become a maintainer and
developer.  (Otherwise, work on HOL Proof General will not continue).

Apart from that there are a few other small improvements.  Check the
CHANGES file in the distribution for full details.

The HOL98 support and much of the work on Proof General 3.1 was
undertaken by David Aspinall while he was visiting ETL, Osaka, Japan,
supported by the British Council and ETL.


@node Old News for 3.0
@unnumberedsec Old News for 3.0

Proof General 3.0 (released November 1999) has many improvements over
2.x releases.

First, there are usability improvements.  The toolbar was somewhat
impoverished before.  It now has twice as many buttons, and includes all
of the useful functions used during proof which were previously hidden
on the menu, or even only available as key-presses.  Key-bindings have
been re-organized, users of previous versions may notice.  The menu has
been redesigned and coordinated with the toolbar, and now gives easy
access to more of the features of Proof General.  Previously several
features were only likely to be discovered by those keen enough to read
this manual!

Second, there are improvements, extensions, and bug fixes in the generic
basis. Proofs which are unfinished and not explicitly closed by a
``save'' type command are supported by the core, if they are allowed by
the prover.  The design of switching the active scripting buffer has
been streamlined.  The management of the queue of commands waiting to be
sent to the shell has been improved, so there are fewer unnecessary
"Proof Process Busy!" messages.  The support for scripting with multiple
files was improved so that it behaves reliably with Isabelle99; file
reading messages can be communicated in both directions now.  The proof
shell filter has been optimized to give hungry proof assistants a better
share of CPU cycles.  Proof-by-pointing has been resurrected; even
though LEGO's implementation is incomplete, it seems worth maintaining
the code in Proof General so that the implementors of other proof
assistants are encouraged to provide support.  For one example, we can
certainly hope for support in Coq, since the CtCoq proof-by-pointing
code has been moved into the Coq kernel lately.  We need a volunteer
from the Coq community to help to do this.

An important new feature in Proof General 3.0 is support for
@uref{http://x-symbol.sourceforge.net/,X-Symbol}, 
which means that real logical symbols, Greek letters,
etc can be displayed during proof development, instead of their ASCII
approximations. This makes Proof General a more serious competitor to
native graphical user interfaces.

Finally, Proof General has become much easier to adapt to new provers
--- it fails gracefully (or not at all!) when particular configuration
variables are unset, and provides more default settings which work
out-of-the-box.  An example configuration for Isabelle is provided,
which uses just 25 or so simple settings.

This manual has been updated and extended for Proof General 3.0.
Amongst other improvements, it has a better description of how to add
support for a new prover.

See the @code{CHANGES} file in the distribution for more information
about the latest improvements in Proof General.  Developers should check
the @code{ChangeLog} in the developer's release for detailed comments on
internal changes.

Most of the work for Proof General 3.0 has been done by David Aspinall.
Markus Wenzel helped with Isabelle support, and provided invaluable
feedback and testing, especially for the improvements to multiple file
handling.  Pierre Courtieu took responsibility from Patrick Loiseleur
for Coq support, although the improvements in both the Coq and LEGO code
for this release were made by David Aspinall.  Markus Wenzel also
provided support for his Isar language, a new proof language for
Isabelle.  David von Oheimb helped to develop and debug the generic
version of his X-Symbol patch which he originally provided for Isabelle.

A new instantiation of Proof General is being worked on for
@emph{Plastic}, a proof assistant being developed at the University of
Durham.



@node History before 3.0
@unnumberedsec History before 3.0
@cindex @code{lego-mode}
@cindex history

It all started some time in 1994. There was no Emacs interface for LEGO.
Back then, Emacs militants worked directly with the Emacs shell to
interact with the LEGO system. 

David Aspinall convinced Thomas Kleymann that programming in
Emacs Lisp wasn't so difficult after all. In fact, Aspinall had already
implemented an Emacs interface for Isabelle with bells and whistles,
called @uref{http://www.proofgeneral.org/~isamode,Isamode}. Soon
after, the package @code{lego-mode} was born. Users were able to develop
proof scripts in one buffer. Support was provided to automatically send
parts of the script to the proof process. The last official version with
the name @code{lego-mode} (1.9) was released in May 1995.


@cindex proof by pointing 
@cindex CtCoq
@cindex Centaur
The interface project really took off the ground in November 1996. Yves
Bertot had been working on a sophisticated user interface for the Coq
system (CtCoq) based on the generic environment Centaur. He visited the
Edinburgh LEGO group for a week to transfer proof-by-pointing
technology. Even though proof-by-pointing is an inherently
structure-conscious algorithm, within a week, Yves Bertot, Dilip Sequeira 
and Thomas Kleymann managed to implement a first prototype of
proof-by-pointing in the Emacs interface for LEGO [BKS97].

@cindex structure editor
@cindex script management

Perhaps we could reuse even more of the CtCoq system. It being a
structure editor did no longer seem to be such an obstacle. Moreover,
to conveniently use proof-by-pointing in actual developments, one would
need better support for script management.

@cindex generic
In 1997, Dilip Sequeira implemented script management in our Emacs
interface for LEGO following the recipe in
[BT98]. Inspired by the project CROAP, the
implementation made some effort to be generic. A working prototype was
demonstrated at UITP'97.

In October 1997, Healfdene Goguen ported @code{lego-mode} to Coq. Part
of the generic code in the @code{lego} package was outsourced (and made
more generic) in a new package called @code{proof}. Dilip Sequeira
provided some LEGO-specific support for handling multiple files and
wrote a few manual pages. The system was reasonably robust and we
shipped out the package to friends.

In June 1998, David Aspinall reentered the picture by providing an
instantiation for Isabelle. Actually, our previous version wasn't quite
as generic as we had hoped. Whereas LEGO and Coq are similar systems in
many ways, Isabelle was really a different beast. Fierce re-engineering
and various usability improvements were provided by Aspinall and
Kleymann to make it easier to instantiate to new proof systems. The
major technical improvement was a truly generic extension of script
management to work across multiple files.

It was time to come up with a better name than just @code{proof}
mode. David Aspinall suggested @emph{Proof General} and set about
reorganizing the file structure to disentangle the Proof General project
from LEGO at last.  He cooked up some images and bolted on a toolbar, so
a naive user can replay proofs without knowing a proof assistant
language or even Emacs hot-keys.  He also designed some web pages, and
wrote most of this manual.  

Proof General 2.0 was the first official release of the improved
program, made in December 1998.

Version 2.1 was released in August 1999.  It was used at the Types
Summer School held in Giens, France in September 1999 (see
@uref{http://www-sop.inria.fr/types-project/types-sum-school.html}).
About 50 students learning Coq, Isabelle, and LEGO used Proof General
for all three systems.  This experience provided invaluable feedback and
encouragement to make the improvements now in Proof General 3.0.

@c Why not adapt Proof General to your favourite proof assitant?



@node Credits
@unnumberedsec Credits
@cindex @code{lego-mode}
@cindex maintenance

The main developers of Proof General have been:

@itemize @bullet
@item @b{David Aspinall},
@item @b{Healfdene Goguen},
@item @b{Thomas Kleymann} and
@item @b{Dilip Sequeira}.
@end itemize

LEGO Proof General (the successor of @code{lego-mode}) was crafted by
Thomas Kleymann and Dilip Sequeira. 
@c
It is presently maintained by David Aspinall and
Paul Callaghan @i{<P.C.Callaghan@@durham.ac.uk>}. 
@c
Coq Proof General was crafted by Healfdene Goguen, with
later contributions from Patrick Loiseleur.
It is now maintained by Pierre Courtieu @i{<courtieu@@lri.fr>}.
@c
Isabelle Proof General was crafted and is being maintained by David
Aspinall @i{<da@@dcs.ed.ac.uk>}.  It has benefited greatly from tweaks
and suggestions by Markus Wenzel @i{<wenzelm@@informatik.tu-muenchen.de>}, 
who crafted and maintains Isabelle/Isar Proof General.  Markus also
added Proof General support inside Isabelle.  David von Oheimb supplied
the original patches for X-Symbol support.

The generic base for Proof General was developed by Kleymann, Sequeira,
Goguen and Aspinall. It follows some of the ideas used in Project
@uref{http://www.inria.fr/croap/,CROAP}. The project to implement a
proof mode for LEGO was initiated in 1994 and coordinated until October
1998 by Thomas Kleymann, becoming generic along the way.  In October
1998, the project became Proof General and has been managed by David
Aspinall since then.

This manual was written by David Aspinall and Thomas Kleymann.  Some
words found their way here from the user documentation of LEGO mode,
prepared by Dilip Sequeira.  Healfdene Goguen supplied some text for Coq
Proof General.  Since Proof General 2.0, this manual has been maintained
and improved by David Aspinall.  Pierre Courtieu wrote the section on
file variables.

The Proof General project has benefited from funding by EPSRC
(Applications of a Type Theory Based Proof Assistant), the EC (Types for
Proofs and Programs) and the support of the LFCS.  Version 3.1 was
prepared whilst David Aspinall was visiting ETL, Japan, supported by the
British Council.

For testing and feedback for older versions of Proof General, thanks go
to Rod Burstall, Martin Hofmann, and James McKinna, and some of those
who continued to help with the latest 3.x series, named next.

@c FIXME HERE!
During the development of Proof General 3.x releases, 
many people helped provide testing and other feedback, 
including the Proof General maintainers,
Paul Callaghan, Pierre Courtieu, and Markus Wenzel, and other folk who
tested pre-releases or sent bug reports, including 
Pascal Brisset,
Martin Buechi,
Matt Fairtlough, 
Kim Hyung Ho,
Pierre Lescanne,
John Longley, 
Tobias Nipkow, 
Leonor Prensa Nieto, 
David von Oheimb,
Randy Pollack,
Robert R. Schneck,
Sebastian Skalberg,
and
Mike Squire.  Thanks to all of you!




@c
@c CHAPTER: Introduction
@c
@node Introducing Proof General
@chapter Introducing Proof General
@cindex proof assistant
@cindex Proof General

@c would like the logo on the title page really but
@c it doesn't seem to work there for html.
@ifhtml
<IMG SRC="ProofGeneral.jpg" ALT="[ Proof General logo ]" >
@end ifhtml

@dfn{Proof General} is a generic Emacs interface for interactive proof
assistants,@footnote{A @dfn{proof assistant} is a computerized helper for
developing mathematical proofs.  For short, we sometimes call it a
@dfn{prover}, although we always have in mind an interactive system
rather than a fully automated theorem prover.} developed at the LFCS in
the University of Edinburgh.  It works best under XEmacs, but can also
be used with GNU Emacs.

You do not have to be an Emacs militant to use Proof General!  

The interface is designed to be very easy to use.  You develop your
proof script@footnote{A @dfn{proof script} is a sequence of commands
 which constructs a proof, usually stored in a file.}
 in-place rather than line-by-line and later reassembling the pieces.
Proof General keeps track of which proof steps have been processed by
the prover, and prevents you editing them accidently.  You can undo
steps as usual.

The aim of Proof General is to provide a powerful and configurable
interface for numerous interactive proof assistants.  We target Proof
General mainly at intermediate or expert users, so that the interface
should be useful for large proof developments.  

Please help us!

Send us comments, suggestsions, or (the best) patches to improve support
for your chosen proof assistant.  Contact us at
@code{proofgen@@dcs.ed.ac.uk}.

If your chosen proof assistant isn't supported, read the accompanying
@i{Adapting Proof General} manual to find out how to configure PG for a
new prover.  

@menu
* Quick start guide::           
* Features of Proof General::   
* Supported proof assistants::  
* Prerequisites for this manual::
* Organization of this manual::
@end menu




@node Quick start guide
@section Quick start guide

Proof General may have been installed for you already. If so, when you
visit a proof script file for your proof assistant, the corresponding
Proof General mode will be invoked automatically: 
@multitable @columnfractions .3 .3 .4
@item       @b{Prover}    @tab @b{Extensions} @tab @b{Mode}
@item       LEGO          @tab @file{.l}      @tab @code{lego-mode}
@item       Coq           @tab @file{.v}      @tab @code{coq-mode}
@item       Isabelle      @tab @file{.thy},@file{.ML} @tab @code{isa-mode}
@item       Isabelle/Isar @tab @file{.thy}    @tab @code{isar-mode}
@item       Phox          @tab @file{.phx}    @tab @code{phox-mode}
@item       HOL98         @tab @file{.sml}    @tab @code{hol98-mode}
@end multitable
(The exact list of Proof Assistants supported may vary according to the
version of Proof General and its local configuration).  You can also
invoke the mode command directly, e.g., type @kbd{M-x lego-mode}, to
turn a buffer into a lego script buffer.

You'll find commands to process the proof script are available from the
toolbar, menus, and keyboard.  Type @kbd{C-h m} to get a list of the
keyboard shortcuts for the current mode.  The commands available should
be easy to understand, but the rest of this manual describes them in
some detail.

The proof assistant itself is started automatically inside Emacs as an
"inferior" process when you ask for some of the proof script to be
processed.  You can also start the proof assistant directly with the
menu command "Start proof assistant".

To follow an example use of Proof General on a LEGO proof, 
@pxref{Walkthrough example in LEGO}.  If you know the syntax for proof
scripts in another theorem prover, you can easily adapt the details 
given there.

If Proof General has not already been installed, you should insert the
line:
@lisp
        (load "@var{proof-general-home}/generic/proof-site.el")
@end lisp
into your @file{~/.emacs} file, where @var{proof-general-home} is the
top-level directory that was created when Proof General was unpacked.

@xref{Obtaining and Installing}, if you need more
information.


@node Features of Proof General
@section Features of Proof General
@cindex Features
@cindex Why use Proof General?

Why would you want to use Proof General?

@c FIXME: would like to keep this synched with web page, really.
@c but web page needs extra markup.

Proof General is designed to be useful for novices and expert users
alike.  It will be useful to you if you use a proof assistant, and you'd
like an interface with the following features: simplified interaction,
script management, multiple file scripting, a script editing mode, proof
by pointing, toolbar and menus, syntax highlighting, real symbols,
functions menu, tags, and finally, adaptability.

Here is an outline of some of these features.   Look in the contents
page or index of this manual to find out about the others!

@itemize @bullet
@item @i{Simplified interaction}@*
  Proof General is designed for proof assistants which have a
  command-line shell interpreter.  When using Proof General, the proof
  assistant's shell is hidden from the user.  Communication takes
  place via three buffers (Emacs text widgets).
Communication takes place via three buffers.  The @dfn{script
buffer} holds input, the commands to construct a proof.  The @dfn{goals
buffer} displays the current list of subgoals to be solved.  The
@dfn{response buffer} displays other output from the proof assistant.
By default, only two of these three buffers are displayed. 
This means that the user normally only sees the output from the most
recent interaction, rather than a screen full of output from the proof
assistant.  

Proof General does not commandeer the proof assistant shell: the user
still has complete access to it if necessary.

For more details, @pxref{Summary of Proof General buffers}
and @pxref{Display customization}.


@item @i{Script management}@*
Proof General colours proof script regions blue when they have 
been processed by the prover, and colours regions red when the prover is
currently processing them.  The appearance of Emacs buffers always
matches the proof assistant's state. Coloured parts of the buffer cannot
be edited.  Proof General has functions for @emph{asserting} or
@emph{retracting} parts of a proof script, which alters the coloured
regions.

For more details, @pxref{Basic Script Management},
@ref{Script processing commands},
and @ref{Advanced Script Management}.
@item @i{Script editing mode}@*
Proof General provides useful facilities for editing proof scripts,
including syntax hilighting and a menu to jump to particular goals,
definitions, or declarations.
Special editing functions send lines of proof script to the proof
assistant, or undo previous proof steps.

For more details, @pxref{Script editing commands},
and @ref{Script processing commands}.
@item @i{Toolbar and menus}@*
A script buffer has a toolbar with navigation buttons for processing
parts of the proof script.  A menu provides further functions for
operations in the proof assistant, as well as customization of Proof
General.

For more details, @pxref{Toolbar commands}, @ref{Proof assistant
commands}, and @ref{Customizing Proof General}.

@item @i{Proof by pointing}@*
Proof General has support for proof-by-pointing and similar features.
Proof by pointing allows you to click on a subterm of a goal to be
proved, and automatically apply an appropriate proof rule or tactic.
Proof by pointing is specific to the proof assistant (and logic) in use;
therefore it is configured mainly on the proof assistant side.  If you
would like to see proof by pointing support for Proof General in a
particular proof assistant, petition the developers of the proof
assistant to provide it.
@c Proof General expects to parse
@c term-structure annotations on the output syntax of the prover.
@c It uses these to construct a message to the prover indicating
@c where the user has clicked, and the proof assistant can
@c response with a suggested tactic.
@end itemize


@node Supported proof assistants
@section Supported proof assistants

Proof General comes ready-customized for these proof assistants:

@c FLAG VERSIONS HERE
@itemize @bullet
@item 
@b{LEGO Proof General} for LEGO Version 1.3.1@*
@xref{LEGO Proof General}, for more details.
@item 
@b{Coq Proof General} for Coq Version 6.3@*
@xref{Coq Proof General}, for more details.
@item 
@b{Isabelle Proof General} for Isabelle2002@*
@xref{Isabelle Proof General}, for more details.
@item 
@b{Isabelle/Isar Proof General} for Isabelle2002*
@xref{Isabelle Proof General}, and documentation supplied with
Isabelle for more details.
@b{HOL Proof General} for HOL98@*
@xref{HOL Proof General}, for more details.
@end itemize
Proof General is designed to be generic, so if you know how
to write regular expressions, you can make:
@itemize @bullet
@item
@b{Your Proof General} for your favourite proof assistant.@*
For more details of how to make Proof General work
with another proof assistant,
see the accompanying manual @i{Adapting Proof General}.
@end itemize
The exact list of Proof Assistants supported may vary according to the
version of Proof General you have and its local configuration; only the
standard instances documented in this manual are listed above.

Note that there is some variation between the features supported by
different instances of Proof General.  The main variation is proof by
pointing, which is only supported in LEGO at the moment.  For advanced
features like this, some extensions to the output routines of the proof
assistant are required, typically.  If you like Proof General, please
help us by asking the implementors of your favourite proof assistant to
support Proof General as much as possible.

@node Prerequisites for this manual
@section Prerequisites for this manual
@cindex Meta
@cindex Alt
@cindex key sequences

This manual assumes that you understand a little about using Emacs, for
example, switching between buffers using @kbd{C-x b} and understanding
that a key sequence like @kbd{C-x b} means "control with x, followed by b".
A key sequence like @kbd{M-z} means "meta with z".  (@key{Meta} may be
labelled @key{Alt} on your keyboard).

The manual also assumes you have a basic understanding of your proof
assistant and the language and files it uses for proof scripts.  But
even without this, Proof General is not useless: you can use the
interface to @emph{replay} proof scripts for any proof assistant without
knowing how to start it up or issue commands, etc.  This is the beauty
of a common interface mechanism.

To get more from Proof General and adapt it to your liking, it helps to
know a little bit about how Emacs lisp packages can be customized via
the Customization mechanism.  It's really easy to use.  For details,
@pxref{How to customize}.  @inforef{Easy customization, ,(xemacs)},
for documentation in XEmacs.

To get the absolute most from Proof General, to improve it or to adapt
it for new provers, you'll need to know a little bit of Emacs lisp.
Emacs is self-documenting, so you can begin from @kbd{C-h} and find out
everything!  Here are some useful commands:

@table @asis
@item @kbd{C-h i}
@code{info}
@item @kbd{C-h m} 
@code{describe-mode}
@item @kbd{C-h b} 
@code{describe-bindings}
@item @kbd{C-h f} 
@code{describe-function}
@item @kbd{C-h v} 
@code{describe-variable}
@end table


@node Organization of this manual
@section Organization of this manual

This manual covers the user-level view and customization of Proof
General.  The accompanying @i{Adapting Proof General} manual considers
adapting Proof General to new proof assistants, and documents some of
the internals of Proof General.

Three appendices of this manual contain some details about obtaining and
installing Proof General and some known bugs.  The contents of these
final chapters is also covered in the files @file{INSTALL} and
@file{BUGS} contained in the distribution.  Refer to those files
for the latest information.

The manual concludes with some references and indexes.  See the table of
contents for full details.







@c
@c CHAPTER: Basic Script Management
@c
@node Basic Script Management
@chapter Basic Script Management

This chapter is an introduction to using the script management
facilities of Proof General.  We begin with a quick walkthrough example,
then describe the concepts and functions in more detail.

@menu
* Walkthrough example in LEGO::  
* Proof scripts::               
* Script buffers::              
* Summary of Proof General buffers::               
* Script editing commands::     
* Script processing commands::  
* Proof assistant commands::    
* Toolbar commands::            
* Interrupting during trace output::
@end menu

@node Walkthrough example in LEGO
@section Walkthrough example in LEGO

Here's a short example in LEGO to see how script management is used.
The file you are asked to type below is included in the distribution as
@file{lego/example.l}.  If you're not using LEGO, substitute some lines
from a simple proof for your proof assistant, or consult the file
called something like @file{foo/example.foo} for proof assistant Foo.

This walkthrough is keyboard based, but you could easily use the toolbar
and menu functions instead.  The best way to learn Emacs key bindings is
by using the menus.  You'll find the keys named below listed on the
menus.

@itemize @bullet
@item
First, find a new file by @kbd{C-x C-f} and typing as the filename
@file{example.l}.  This should load LEGO Proof General and the toolbar
and Proof General menus will appear.  You should have an empty buffer
displayed.
@end itemize

The notation @kbd{C-x C-f} means control key with `x' followed by
control key with `f'.  This is a standard notation for Emacs key
bindings, used throughout this manual.  This function also
appears on the @code{File} menu of Emacs.  The remaining commands
used will be on the @code{Proof-General} menu.

If you're not using LEGO, you must choose a different file extension,
appropriately for your proof assistant.  If you don't know what to use,
see the previous chapter for the list of supported assistants and file
extensions.

@itemize @bullet
@item
Turn on @dfn{electric terminator} by typing @kbd{C-c ;} and
enter:
@lisp
Module example Import lib_logic;
@end lisp
This first command defines a file header and tells LEGO to use logic; 
these steps are usually not necessary in other proof assistants.
@end itemize

Electric terminator sends commands to the proof assistant as you type
them.  The exact key binding is based on the terminator used for your
proof assistant, but you can always check the menu if you're not sure.

Electric terminator mode is popular, but not enabled by default because
of the principle of least surprise.  You can customize Proof General to
enable it everytime if you want, @xref{Customizing Proof General}.  In
XEmacs, this is particularly easy: just use the menu item @code{Options
-> Save Options} to save some common options while using Proof General.

The @code{Module} command should now be lit in pink (or inverse video if
you don't have a colour display).  As LEGO imports each module, a line
will appear in the minibuffer showing the creation of context
marks. Eventually the command should turn blue, indicating that LEGO has
successfully processed it.

@itemize @bullet
@item
Next type (on a new line if you like):
@lisp
Goal bland_commutes: @{A,B:Prop@} (and A B) -> (and B A);
@end lisp
@end itemize

The goal should be displayed in the goals buffer.

@itemize @bullet
@item 
Now type:
@lisp
Intros;
@end lisp
@end itemize
This will update the goals buffer.

But whoops! That was the wrong command.

@itemize @bullet
@item
Press @kbd{C-c C-BS} to pretend that didn't happen.
@end itemize
Note: @kbd{BS} means the backspace key.  This key press sends an undo
command to LEGO, and deletes the @code{Intros;} command from the proof
script.  If you just want to undo without deleting, you can type
@kbd{C-c C-u} instead, or use the toolbar navigation button.

@itemize @bullet
@item
Instead, let's try:
@lisp
intros; andI;
@end lisp
We've used the conjunction-introduction rule.

To finish off, use these commands:
@lisp
Refine H; intros; Immed; Refine H; intros; Immed;
@end lisp
@end itemize
Now you should see LEGO display the QED message.

@itemize @bullet
@item
Finally, type:
@lisp
Save bland_commutes;
@end lisp
@end itemize

This last command closes the proof and saves the proved theorem.

Moving the mouse pointer over the locked region now reveals that the
entire proof has been aggregated into a single segment. This reflects
the fact that LEGO has thrown away the history of the proof, so if we
want to undo now, the whole proof must be retracted.

@itemize  @bullet
@item 
Suppose we decide to call the goal something more sensible. Move the
cursor up into the locked region, somewhere between @samp{Goal} and
@samp{Save}, enter @kbd{C-c C-RET}.  
@end itemize

You see that the locked segment for the whole proof is now unlocked (and
uncoloured): it is transferred back into the editing region.

The command @kbd{C-c C-RET} moves the end of the locked region to the
cursor position, sending undoing commands or proof commands as
necessary.

@itemize @bullet
@item 
Now correct the goal name, for example:
@lisp
Goal and_commutes: @{A,B:Prop@} (and A B) -> (and B A);
@end lisp
Move the cursor to the end of the buffer, and
type @kbd{C-c C-RET} again.  
@end itemize

Proof General queues the commands for processing and executes them one
by one.  You should see the proof turn pink, then quickly command by
command it is turned blue.  The progress of pink to blue can be
much slower with long and complicated proofs!



@node Proof scripts
@section Proof scripts
@cindex proof script
@cindex scripting

A @dfn{proof script} is a sequence of commands which constructs
definitions, declarations, theories, and proofs in a proof
assistant. Proof General is designed to work with text-based
@i{interactive} proof assistants, where the mode of working is usually a
dialogue between the human and the proof assistant.  

Primitive interfaces for proof assistants simply present a @dfn{shell}
(command interpreter) view of this dialogue: the human repeatedly types
commands to the shell until the proof is completed.  The system responds
at each step, perhaps with a new list of subgoals to be solved, or
perhaps with a failure report.  Proof General manages the dialogue to
show the human only the information which is relevant at each step.

Often we want to keep a record of the proof commands used to prove a
theorem, to build up a library of proved results.  An easy way to store
a proof is to keep a text file which contains a proof script; proof
assistants usually provide facilities to read a proof script from a file
instead of the terminal.  Using the file, we can @dfn{replay} the proof
script to prove the theorem again.
@c Re-playing a proof script is a non-interactive procedure,
@c since it is supposed to succeed.

Using only a primitive shell interface, it can be tedious to construct
proof scripts with cut-and-paste.  Proof General helps out by issuing
commands directly from a proof script file, while it is being written
and edited.  Proof General can also be used conveniently to replay a
proof step-by-step, to see the progress at each stage.
@c developing them in proof script files.

@dfn{Scripting} is the process of building up a proof script file or
replaying a proof.  When scripting, Proof General sends proof commands
to the proof assistant one at a time, and prevents you from editing
commands which have been successfully completed by the proof assistant,
to keep synchronization.  Regions of the proof script are analysed
based on their syntax and the behaviour of the proof assistant after each
proof command.


@node Script buffers
@section Script buffers
@cindex script buffer
@cindex proof script mode

A @dfn{script buffer} is a buffer displaying a proof script.  Its Emacs
mode is particular to the proof assistant you are using (but it inherits
from @dfn{proof-mode}).


A script buffer is divided into three regions: @emph{locked},
@emph{queue} and @emph{editing}.  The proof commands
in the script buffer can include a number of
@emph{Goal-save sequences}.

@menu
* Locked queue and editing regions::  
* Goal-save sequences::         
* Active scripting buffer::     
@end menu


@node Locked queue and editing regions
@subsection Locked, queue, and editing regions
@cindex Locked region
@cindex Queue region
@cindex Editing region
@cindex blue text
@cindex pink text


The three regions that a script buffer is divided into are: @c 

@itemize @bullet
@item The @emph{locked} region, which appears in blue (underlined on monochrome
displays) and contains commands which have been sent to the proof
process and verified. The commands in the locked region cannot be
edited.

@item The @emph{queue} region, which appears in pink (inverse video) and contains
commands waiting to be sent to the proof process. Like those in the
locked region, these commands can't be edited.

@item The @emph{editing} region, which contains the commands the user is working
on, and can be edited as normal Emacs text.
@end itemize

These three regions appear in the buffer in the order above; that is,
the locked region is always at the start of the buffer, and the editing
region always at the end. The queue region only exists if there is input
waiting to be processed by the proof process.

Proof General has two fundamental operations which transfer commands
between these regions: @emph{assertion} (or processing) and
@emph{retraction} (or undoing).

@cindex Assertion
@strong{Assertion} causes commands from the editing region to be
transferred to the queue region and sent one by one to the proof
process. If the command is accepted, it is transferred to the locked
region, but if an error occurs it is signalled to the user, and the
offending command is transferred back to the editing region together
with any remaining commands in the queue.

Assertion corresponds to processing proof commands, and makes the locked
region grow.

@cindex Retraction
@strong{Retraction} causes commands to be transferred from the locked
region to the editing region (again via the queue region) and the
appropriate 'undo' commands to be sent to the proof process.

Retraction corresponds to undoing commands, and makes the locked region
shrink.  For details of the commands
available for doing assertion and retraction,
@xref{Script processing commands}.


@node Goal-save sequences
@subsection Goal-save sequences
@cindex goal
@cindex save
@cindex goal-save sequences

A proof script contains a sequence of commands used to prove one or more
theorems.

As commands in a proof script are transferred to the locked region, they
are aggregated into segments which constitute the smallest units which
can be undone. Typically a segment consists of a declaration or
definition, or all the text from a @dfn{goal} command to the
corresponding @dfn{save} command, or the individual commands in the
proof of an unfinished goal.  As the mouse moves over the the region,
the segment containing the pointer will be highlighted.

Proof General therefore assumes that the proof script has a series of
proofs which look something like this:
@lisp
   goal @var{mythm} is @var{G}
   @dots{}
   save theorem @var{mythm}
@end lisp
interspersed with comments, definitions, and the like.  Of course, the
exact syntax and terminology will depend on the proof assistant you use.

The name @var{mythm} can appear in a menu for the proof script to help
quickly find a proof (@pxref{Support for function menus}).

@c Proof General recognizes the goal-save sequences in proof scripts.
@c once a goal-save region has been fully processed by the proof assistant,
@c it is treated as atomic when undoing proof steps.  This reflects the
@c fact that most proof assistants discard the history of a proof once a it
@c is completed or once a new proof is begun.


@node Active scripting buffer
@subsection Active scripting buffer
@cindex active scripting buffer

You can edit as many script buffers as you want simultaneously, but only
one buffer at a time can be used to process a proof script
incrementally: this is the @dfn{active scripting buffer}.

The active scripting buffer has a special indicator: the word
@code{Scripting} appears in its mode line.  

When you use a scripting command, it will automatically turn a buffer
into the active scripting mode.  You can also do this by hand, via the
menu command 'Toggle Scripting' or the key @kbd{C-c C-s}.

@table @asis
@item @kbd{C-c C-s}
@code{proof-toggle-active-scripting}
@end table

When active scripting mode is turned on, several things may happen to
get ready for scripting (exactly what happens depends on which proof
assistant you are using and some user settings).  First, the proof
assistant is started if it is not already running.  Second, a command is
sent to the proof assistant to change directory to the directory of the
current buffer.  If the current buffer corresponds to a file, this is
the directory the file lives in.  This is in case any scripting commands
refer to files in the same directory as the script.  The third thing
that may happen is that you are prompted to save some unsaved buffers.
This is in case any scripting commands may read in files which you are
editing.  Finally, some proof assistants may automatically read in
files which the current file depends on implicitly.  In Isabelle, for
example, there is an implicit dependency between a @code{.ML} script
file and a @code{.thy} theory file which defines its theory.

If you have a partly processed scripting buffer and use @kbd{C-c C-s},
or you attempt to use script processing in a new buffer, Proof General
will ask you if you want to retract what has been proved so far,
@code{Scripting incomplete in buffer myproof.l, retract?}
or if you want to process the remainder of the active buffer, 
@code{Completely process buffer myproof.l instead?}
before you can start scripting in a new buffer.  If you refuse to do
either, Proof General will give an error message: 
@code{Cannot have more than one active scripting buffer!}.

To turn off active scripting, the buffer must be completely processed
(all blue), or completely unprocessed.  There are two reasons for this.
First, it would certainly be confusing if it were possible to split
parts of a proof arbitrarily between different buffers; the dependency
between the commands would be lost and it would be tricky to replay the
proof.@footnote{Some proof assistants provide some level of support for
switching between multiple concurrent proofs, but Proof General does not
use this.  Generally the exact context for such proofs is hard to define
to easily split them into multiple files.}  Second, we want to interface
with file management in the proof assistant.  Proof General assumes that
a proof assistant may have a notion of which files have been processed,
but that it will only record files that have been @i{completely}
processed.  For more explanation of the handling of multiple files,
@xref{Switching between proof scripts}.

@c TEXI DOCSTRING MAGIC: proof-toggle-active-scripting
@deffn Command proof-toggle-active-scripting &optional arg
Toggle active scripting mode in the current buffer.@*
With @var{arg}, turn on scripting iff @var{arg} is positive.
@end deffn




@node Summary of Proof General buffers
@section Summary of Proof General buffers
@cindex shell buffer
@cindex goals buffer
@cindex response buffer
@cindex proof by pointing

Proof General manages several kinds of buffers in Emacs.  Here is a
summary of the different kinds of buffers you will use when developing
proofs.

@itemize @bullet
@item The @dfn{proof shell buffer} is an Emacs shell buffer
 used to run your proof assistant.  Usually it is hidden from view
 (but @pxref{Escaping script management}).
 Communication with the proof shell takes place via two or three
 intermediate buffers.
@item  A @dfn{script buffer}, as we have explained, is a buffer for editing a
 proof script.  The @dfn{active scripting buffer} is the script buffer
 which is currently being used to send commands to the proof shell.
@item The @dfn{goals buffer} displays the list of subgoals to be
 solved for a proof in progress.  During a proof it is usually
 displayed together with the script buffer.
 The goals buffer has facility for @dfn{proof-by-pointing}.
@item The @dfn{response buffer} displays other output from the proof
 assistant, for example error messages or informative messages.
 The response buffer is displayed whenever Proof General puts
 a new message in it.
@item The @dfn{trace buffer} is a special version of the response
 buffer.  It may be used to display unusual debugging output from the
 prover, for example, tracing proof tactics or rewriting procedures.
 This buffer is also displayed whenever Proof General puts a new message
 in it (although it may be quickly replaced with the response or goals
 buffer in two-buffer mode).
@end itemize

Normally Proof General will automatically reveal and hide the goals and
response buffers as necessary during scripting.  However there are ways
to customize the way the buffers are displayed (@pxref{Display
customization}).

The menu @code{Proof General -> Buffers} provides a convenient way to
display or switch to one of the four buffers: active scripting, goals,
response, or shell.

@c When
@c Proof General sees an error in the shell buffer, it will highlight the
@c error and display the buffer automatically.


@c This facility was not added:
@c
@c Optionally, the goals buffer and script buffer can be identified
@c @pxref{Identify goals and response}.  The disadvantage of this is that
@c the goals display can be replaced by other messages, so you must ask for
@c it to be refreshed.  The advantage is that it is simpler to deal with
@c fewer Emacs buffers.



@node Script editing commands
@section Script editing commands

Proof General provides a few functions for editing proof scripts.  The
generic functions mainly consist of commands to navigate within the
script.  Specific proof assistant code may add more to these basics.

@findex indent-for-tab-command
@vindex proof-script-indent
Indentation is controlled by the user option @code{proof-script-indent}
(@pxref{User options}).  When indentation is enabled, Proof General
will indent lines of proof script with the usual Emacs functions,
particularly @kbd{TAB}, @code{indent-for-tab-command}.
@c FIXME: remove when indentation is fixed.
Unfortunately, indentation in Proof General @value{version} is somewhat
slow.  Therefore with large proof scripts, we recommend
@code{proof-script-indent} is turned off.

Here are the commands for moving around in a proof script,
with their default key-bindings:
@kindex C-c C-a
@kindex C-c C-e
@kindex C-c C-.
@table @kbd
@item C-c C-a
@code{proof-goto-command-start}
@item C-c C-e
@code{proof-goto-command-end}
@item C-c C-.
@code{proof-goto-end-of-locked}
@end table

@c TEXI DOCSTRING MAGIC: proof-goto-command-start
@deffn Command proof-goto-command-start 
Move point to start of current (or final) command of the script.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-goto-command-end
@deffn Command proof-goto-command-end 
Set point to end of command at point.
@end deffn

@vindex proof-terminal-char
The variable @code{proof-terminal-char} is a prover-specific character
to terminate proof commands.  LEGO and Isabelle use a semicolon,
@samp{;}. Coq employs a full-stop @samp{.}.

@c TEXI DOCSTRING MAGIC: proof-goto-end-of-locked
@deffn Command proof-goto-end-of-locked &optional switch
Jump to the end of the locked region, maybe switching to script buffer.@*
If interactive or @var{switch} is non-nil, switch to script buffer first.
@end deffn

During the course of a large proof, it may be useful to copy previous
commands.  As you move the mouse over previous portions of the script,
you'll notice that each proof command is highlighted individually.
(Once a goal...save sequence is ``closed'', the whole sequence is
highlighted).  There is a useful mouse binding for copying the
highlighted command under the mouse:

@kindex C-button1
@table @kbd
@item C-button1 
@code{proof-mouse-track-insert}
@end table

@c TEXI DOCSTRING MAGIC: proof-mouse-track-insert


@deffn Command proof-mouse-track-insert event
Copy highlighted command under the mouse to point.  Ignore comments.@*
If there is no command under the mouse, behaves like @code{mouse-track-insert}.
@end deffn
Read the documentation in Emacs to find out about the normal behaviour
of @code{proof-mouse-track-insert}, if you don't already know what it
does.


@node Script processing commands
@section Script processing commands
@kindex C-c C-n
@kindex C-c C-u
@kindex C-c C-BS
@kindex C-c C-b
@kindex C-c C-r
@kindex C-c C-RET
@cindex prefix argument

Here are the commands for asserting and retracting portions of the proof
script, together with their default key-bindings.  Sometimes assertion
and retraction commands can only be issued when the queue is empty.  You
will get an error message @code{Proof Process Busy!} if you try to
assert or retract when the queue is being processed.@footnote{In fact,
this is an unnecessary restriction imposed by the original design of
Proof General.  There is nothing to stop future versions of Proof
General allowing the queue region to be extended or shrunk, whilst the
prover is processing it.  Proof General 3.0 already relaxes the original
design, by allowing successive assertion commands without complaining.}

@table @kbd
@item C-c C-n
@code{proof-assert-next-command-interactive}
@item C-c C-u
@code{proof-undo-last-successful-command}
@item C-c C-BS
@code{proof-undo-and-delete-successful-command}
@item C-c C-RET
@code{proof-goto-point}
@item C-c C-b
@code{proof-process-buffer}
@item C-c C-r
@code{proof-retract-buffer}
@item C-c @var{terminator-character}
@code{proof-electric-terminator-toggle}
@end table

The last command, @code{proof-electric-terminator-toggle}, is triggered
using the character which terminates proof commands for your proof
assistant's script language.  For LEGO and Isabelle, use @kbd{C-c ;},
for Coq, use @kbd{C-c .}.  This not really a script processing
command. Instead, if enabled, it causes subsequent key presses of
@kbd{;} or @kbd{.} to automatically activate
@code{proof-assert-next-command-interactive} for convenience.

Rather than use a file command inside the proof assistant to read a
proof script, a good reason to use @kbd{C-c C-b}
(@code{proof-process-buffer}) is that with a faulty proof script (e.g.,
a script you are adapting to prove a different theorem), Proof General
will stop exactly where the proof script fails, showing you the error
message and the last processed command.  So you can easily continue
development from exactly the right place in the script.

Here is the full set of script processing commands.

@c TEXI DOCSTRING MAGIC: proof-assert-next-command-interactive
@deffn Command proof-assert-next-command-interactive 
Process until the end of the next unprocessed command after point.@*
If inside a comment, just process until the start of the comment.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-undo-last-successful-command
@deffn Command proof-undo-last-successful-command 
Undo last successful command at end of locked region.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-undo-and-delete-last-successful-command
@deffn Command proof-undo-and-delete-last-successful-command 
Undo and delete last successful command at end of locked region.@*
Useful if you typed completely the wrong command.
Also handy for proof by pointing, in case the last proof-by-pointing
command took the proof in a direction you don't like.

Notice that the deleted command is put into the Emacs kill ring, so
you can use the usual @samp{yank} and similar commands to retrieve the
deleted text.
@end deffn


@c TEXI DOCSTRING MAGIC: proof-goto-point
@deffn Command proof-goto-point 
Assert or retract to the command at current position.@*
Calls @code{proof-assert-until-point} or @code{proof-retract-until-point} as
appropriate.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-process-buffer
@deffn Command proof-process-buffer 
Process the current (or script) buffer, and maybe move point to the end.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-retract-buffer
@deffn Command proof-retract-buffer 
Retract the current buffer, and maybe move point to the start.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-electric-terminator-toggle
@deffn Command proof-electric-terminator-toggle arg
Toggle @samp{@code{proof-electric-terminator-enable}}. With @var{arg}, turn on iff ARG>0.@*
This function simply uses @code{customize-set-variable} to set the variable.
It was constructed with @samp{@code{proof-deftoggle-fn}}.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-assert-until-point-interactive
@deffn Command proof-assert-until-point-interactive 
Process the region from the end of the locked-region until point.@*
Default action if inside a comment is just process as far as the start of
the comment.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-retract-until-point-interactive
@deffn Command proof-retract-until-point-interactive &optional delete-region
Tell the proof process to retract until point.@*
If invoked outside a locked region, undo the last successfully processed
command.  If called with a prefix argument (@var{delete-region} non-nil), also
delete the retracted region from the proof-script.
@end deffn

As experienced Emacs users will know, a @i{prefix argument} is a numeric
argument supplied by some key sequence typed before a command key
sequence.  You can supply a specific number by typing @key{Meta} with
the digits, or a ``universal'' prefix of @kbd{C-u}.  See
@inforef{Arguments, ,(xemacs)} for more details.  Several Proof General
commands, like @code{proof-retract-until-point-interactive}, may accept
a @i{prefix argument} to adjust their behaviour somehow.


@node Proof assistant commands
@section Proof assistant commands
@kindex C-c C-p
@kindex C-c C-h
@kindex C-c C-c
@kindex C-c C-v
@kindex C-c C-f
@kindex C-c C-t

There are several commands for interacting with the proof assistant away
from a proof script.  Here are the key-bindings and functions.

@table @kbd
@item C-c C-l
@code{proof-display-some-buffers}
@item C-c C-p
@code{proof-prf}
@item C-c C-t
@code{proof-ctxt}
@item C-c C-h
@code{proof-help}
@item C-c C-f
@code{proof-find-theorems}
@item C-c C-c
@code{proof-interrupt-process}
@item C-c C-v
@code{proof-minibuffer-cmd}
@end table


@c TEXI DOCSTRING MAGIC: proof-display-some-buffers
@deffn Command proof-display-some-buffers 
Display the reponse or goals buffer, toggling between them.@*
Also move point to the end of the response buffer.
If in three window or multiple frame mode, display both buffers.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-prf
@deffn Command proof-prf 
Show the current proof state.@*
Issues a command to the assistant based on @code{proof-showproof-command}.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-ctxt
@deffn Command proof-ctxt 
Show the current context.@*
Issues a command to the assistant based on @code{proof-context-command}.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-help
@deffn Command proof-help 
Show a help or information message from the proof assistant.@*
Typically, a list of syntax of commands available.
Issues a command to the assistant based on @code{proof-info-command}.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-find-theorems
@deffn Command proof-find-theorems arg
Search for items containing given constants.@*
Issues a command based on @var{arg} to the assistant, using @code{proof-find-theorems-command}.
The user is prompted for an argument.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-interrupt-process
@deffn Command proof-interrupt-process 
Interrupt the proof assistant.  Warning! This may confuse Proof General.@*
This sends an interrupt signal to the proof assistant, if Proof General
thinks it is busy.  

This command is risky because when an interrupt is trapped in the
proof assistant, we don't know whether the last command succeeded or
not.  The assumption is that it didn't, which should be true most of
the time, and all of the time if the proof assistant has a careful
handling of interrupt signals.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-minibuffer-cmd
@deffn Command proof-minibuffer-cmd cmd
Prompt for a command in the minibuffer and send it to proof assistant.@*
The command isn't added to the locked region.

If a prefix arg is given and there is a selected region, that is
pasted into the command.  This is handy for copying terms, etc from
the script.

If @samp{@code{proof-strict-state-preserving}} is set, and @samp{@code{proof-state-preserving-p}} 
is configured, then the latter is used as a check that the command
will be safe to execute, in other words, that it won't ruin
synchronization.  If when applied to the command it returns false,
then an error message is given.

@var{warning}: this command risks spoiling synchronization if the test
@samp{@code{proof-state-preserving-p}} is not configured, if it is
only an approximate test, or if @samp{@code{proof-strict-state-preserving}}
is off (nil).
@end deffn

As if the last two commands weren't risky enough, there's also a command
which explicitly adjusts the end of the locked region, to be used in
extreme circumstances only.  @xref{Escaping script management}.

There are a few commands for stopping, starting, and restarting the
proof assistant process which have menu entries but no key-bindings.
As with any Emacs command, you can invoke these with @kbd{M-x}.

Here's a tip: if you accidently kill one of the Proof General special
buffers (goals or response), exiting the proof assistant and restarting
it will solve the problem.

@c TEXI DOCSTRING MAGIC: proof-shell-start
@deffn Command proof-shell-start 
Initialise a shell-like buffer for a proof assistant.

Also generates goal and response buffers.
Does nothing if proof assistant is already running.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-shell-restart
@deffn Command proof-shell-restart 
Clear script buffers and send @code{proof-shell-restart-cmd}.@*
All locked regions are cleared and the active scripting buffer
deactivated.  

If the proof shell is busy, an interrupt is sent with
@code{proof-interrupt-process} and we wait until the process is ready.

The restart command should re-synchronize Proof General with the proof
assistant, without actually exiting and restarting the proof assistant
process.

It is up to the proof assistant how much context is cleared: for
example, theories already loaded may be "cached" in some way,
so that loading them the next time round only performs a re-linking
operation, not full re-processing.  (One way of caching is via
object files, used by Lego and Coq).
@end deffn

@c TEXI DOCSTRING MAGIC: proof-shell-exit
@deffn Command proof-shell-exit 
Query the user and exit the proof process.

This simply kills the @code{proof-shell-buffer} relying on the hook function
@code{proof-shell-kill-function} to do the hard work.
@end deffn



@node Toolbar commands
@section Toolbar commands

The toolbar provides a selection of functions for asserting and
retracting portions of the script, issuing non-scripting commands, and
inserting "goal" and "save" type commands.  The latter functions are not
available on keys, but are available from the from the menu, or via
@kbd{M-x}, as well as the toolbar.

@c TEXI DOCSTRING MAGIC: proof-issue-goal
@deffn Command proof-issue-goal arg
Write a goal command in the script, prompting for the goal.@*
Issues a command based on @var{arg} to the assistant, using @code{proof-goal-command}.
The user is prompted for an argument.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-issue-save
@deffn Command proof-issue-save arg
Write a save/qed command in the script, prompting for the theorem name.@*
Issues a command based on @var{arg} to the assistant, using @code{proof-save-command}.
The user is prompted for an argument.
@end deffn


@node Interrupting during trace output
@section Interrupting during trace output

If your prover generates output which is recognized as tracing output in
Proof General, you may need to know about a special provision for
interrupting the prover process.
@c %
If the trace output is voluminous, perhaps looping, it may be difficult
to interrupt with the ordinary @kbd{C-c C-c}
(@code{proof-interrupt-process}) or the corresponding button/menu.  In
this case, you should try Emacs's @b{quit key}, @kbd{C-g}.  This will
cause a quit in any current editing commands, as usual, but during
tracing output it will also send an interrupt signal to the prover.
Hopefully this will stop the tracing output, and Emacs should catch up
after a short delay.

Here's an explanation of the reason for this special provision.  When
large volumes of output from the prover arrive quickly in Emacs, as
typically is the case during tracing (especially tracing looping
tactics!), Emacs may hog the CPU and spend all its time updating the
display with the trace output.  This is especially the case when
features like output fontification and X-Symbol display are active.  If
this happens, ordinary user input in Emacs is not processed, and it
becomes difficult to do normal editing.  The root of the problem is that
Emacs runs in a single thread, and pending process output is dealt with
before pending user input.  Whether or not you see this problem depends
partly on the processing power of your machine (or CPU available to
Emacs when the prover is running).  One way to test is to start an Emacs
shell with @kbd{M-x shell} and type a command such as @code{yes} which
produces output indefinitely.  Now see if you can interrupt the process!
(Warning --- on slower machines especially, this can cause lockups, so
use a fresh Emacs.)



@c
@c CHAPTER: Proof by Pointing
@c 
@node Proof by Pointing
@chapter Proof by Pointing

This chapter describes what you can do from inside the goals buffer,
providing support for these features exists for your proof assistant.
As of Proof General 3.0, it only exists for LEGO.  If you would like to
see proof by pointing support for Proof General in another proof
assistant, please petition the developers of that proof assistant to
provide it!

@menu
* Goals buffer commands::
@end menu

@node Goals buffer commands
@section Goals buffer commands

When you are developing a proof, the input focus (Emacs cursor) is
usually on the script buffer.  Therefore Proof General binds mouse
buttons for commands in the goals buffer, to avoid the need to move the
cursor between buffers.

The mouse bindings are these:

@table @kbd
@item button2
@code{pbp-button-action}
@item C-button2
@code{proof-undo-and-delete-last-successful-command}
@item button3
@code{pbp-yank-subterm}
@end table

Where @kbd{button2} indicates the middle mouse button, and @kbd{button3}
indicates the right hand mouse button.

The idea is that you can automatically construct parts of a proof by
clicking.  Using the middle mouse button asks the proof assistant to try
to do a step in the proof, based on where you click.  If you don't like
the command which was inserted into the script, you can use the control
key with the middle button to undo the step, and delete it from your
script.

Note that proof-by-pointing may construct several commands in one go.
These are sent back to the proof assistant altogether and appear as a
single step in the proof script.  However, if the proof is later
replayed (without using PBP), the proof-by-pointing constructions will
be considered as separate proof commands, as usual.

@c TEXI DOCSTRING MAGIC: pbp-button-action

@deffn Command pbp-button-action event
Construct a proof-by-pointing command based on the mouse-click @var{event}.@*
This function should be bound to a mouse button in the Proof General
goals buffer.

The @var{event} is used to find the smallest subterm around a point.  A
position code for the subterm is sent to the proof assistant, to ask
it to construct an appropriate proof command.  The command which is
constructed will be inserted at the end of the locked region in the
proof script buffer, and immediately sent back to the proof assistant.
If it succeeds, the locked region will be extended to cover the
proof-by-pointing command, just as for any proof command the 
user types by hand.
@end deffn

Proof-by-pointing uses markup describing the term structure of the
concrete syntax output by the proof assistant.  This markup is useful in
itself: it allows you to explore the structure of a term using the mouse
(the smallest subexpression that the mouse is over is highlighted), and
easily copy subterms from the output to a proof script.

The right-hand mouse button provides this convenient way to copy
subterms from the goals buffer, using the function
@code{pbp-yank-subterm}.

@c TEXI DOCSTRING MAGIC: pbp-yank-subterm

@deffn Command pbp-yank-subterm event
Copy the subterm indicated by the mouse-click @var{event}.@*
This function should be bound to a mouse button in the Proof General
goals buffer.

The @var{event} is used to find the smallest subterm around a point.  The
subterm is copied to the @code{kill-ring}, and immediately yanked (copied)
into the current buffer at the current cursor position.

In case the current buffer is the goals buffer itself, the yank
is not performed.  Then the subterm can be retrieved later by an
explicit yank.
@end deffn
@c Proof General expects to parse
@c term-structure annotations on the output syntax of the prover.
@c It uses these to construct a message to the prover indicating
@c where the user has clicked, and the proof assistant can
@c response with a suggested tactic.





@c
@c CHAPTER: Advanced Script Management
@c
@node Advanced Script Management
@chapter Advanced Script Management
@cindex Multiple Files

If you are working with large proof developments, you may want to know
about the advanced script management features of Proof General covered
in this chapter.

Large developments may contain files with many long proofs.  Proof
General provides functions that let you hide completed proofs from view,
temporarily.  

Large proof developments are typically spread across various files which
depend on each other in some way.  Proof General knows enough about the
dependencies to allow script management across multiple files.
With large developments particularly, users may occasionally need to
escape from script management, in case Proof General loses
synchronization with the proof assistant.  Proof General provides
you with several escape mechanisms if you want to do this.

@menu
* Visibility of completed proofs::
* Switching between proof scripts::  
* View of processed files ::    
* Retracting across files::     
* Asserting across files::      
* Automatic multiple file handling::
* Escaping script management::
@end menu

@node Visibility of completed proofs
@section Visibility of completed proofs
@cindex Visibility of proofs

Large developments may consist of large files with many proofs.
To help see what has been proved without the detail of the
proof itself, Proof General can hide completed proofs.

You can toggle the visibility of a proof by using a context sensitive
menu triggered by @b{clicking the right mouse button on a completed
proof}, or the key @kbd{C-c v}, which runs @code{pg-toggle-visibility}.


You can also select the ``disappearing proofs'' mode from the menu,
@lisp
  Proof-General -> Options -> Disappearing Proofs
@end lisp
This automatically hides each proof as it is completed by the
proof assistant.

Finally, two menu commands in the main Proof-General menu,
@emph{Show proofs} and @emph{Hide proofs} apply to all the completed
proofs in the buffer.

Notice that by design, this feature only applies to completed proofs,
@emph{after} they have been processed by the proof assistant.  When
files are first visited in Proof General, no information is stored about
proof boundaries.

The relevant elisp functions and settings are mentioned below.

@c TEXI DOCSTRING MAGIC: pg-toggle-visibility
@deffn Command pg-toggle-visibility 
Toggle visibility of region under point.
@end deffn

@c TEXI DOCSTRING MAGIC: pg-show-all-proofs
@deffn Command pg-show-all-proofs 
Display all completed proofs in the buffer.
@end deffn

@c TEXI DOCSTRING MAGIC: pg-hide-all-proofs
@deffn Command pg-hide-all-proofs 
Hide all completed proofs in the buffer.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-disappearing-proofs
@defopt proof-disappearing-proofs 
Non-nil causes Proof General to hide proofs as they are completed.

The default value is @code{nil}.
@end defopt


@node Switching between proof scripts
@section Switching between proof scripts
@cindex Switching between proof scripts

Basic modularity in large proof developments can be achieved by
splitting proof scripts across various files. Let's assume that you are
in the middle of a proof development. You are working on a soundness
proof of Hoare Logic in a file called@footnote{The suffix may depend of
the specific proof assistant you are using e.g, LEGO's proof script
files have to end with @file{.l}.} @file{HSound.l}. It
depends on a number of other files which develop underlying
concepts e.g. syntax and semantics of expressions, assertions,
imperative programs. You notice that the current lemma is too difficult
to prove because you have forgotten to prove some more basic properties
about determinism of the programming language. Or perhaps a previous
definition is too cumbersome or even wrong.

At this stage, you would like to visit the appropriate file, say
@file{sos.l} and retract to where changes are required. Then, using
script management, you want to develop some more basic theory in
@file{sos.l}. Once this task has been completed (possibly involving
retraction across even earlier files) and the new development has been
asserted, you want to switch back to @file{HSound.l} and replay to the
point you got stuck previously.

Some hours (or days) later you have completed the soundness proof and
are ready to tackle new challenges. Perhaps, you want to prove a
property that builds on soundness or you want to prove an orthogonal
property such as completeness.

Proof General lets you do all of this while maintaining the consistency
between proof script buffers and the state of the proof assistant.
However, you cannot have more than one buffer where only a fraction of
the proof script contains a locked region. Before you can employ script
management in  another proof script buffer, you must either fully assert
or retract the current script buffer.

@node View of processed files 
@section  View of processed files

Proof General tries to be aware of all files that the proof assistant
has processed or is currently processing.  In the best case, it relies
on the proof assistant explicitly telling it whenever it processes a new
file which corresponds@footnote{For example, LEGO generates additional
compiled (optimised) proof script files for efficiency.} to a file
containing a proof script.

If the current proof script buffer depends on background material from
other files, proof assistants typically process these files
automatically. If you visit such a file, the whole file is locked as
having been processed in a single step.  From the user's point of view,
you can only retract but not assert in this buffer. Furthermore,
retraction is only possible to the @emph{beginning} of the buffer.
@c This isn't strictly true, is it?  We lock off buffers atomically,
@c but spans in them to start with stay there.  (Only meaningful
@c for reading currently active scripting file)

Unlike a script buffer that has been processed step-by-step via Proof
General, automatically loaded script buffers do not pass through a
``red'' phase to indicate that they are currently being processed.  This
is a limitation of the present implementation.  Proof General locks a
buffer as soon as it sees the appropriate message from the proof
assistant.  Different proof assistants may use different messages:
either @emph{early locking} when processing a file begins (e.g. LEGO) or
@emph{late locking} when processing a file ends (e.g. Isabelle).

With @emph{early locking}, you may find that a script which has only
been partly processed (due to an error or interrupt, for example), is
wrongly completely locked by Proof General.  Visit the file and retract
back to the start to fix this.

With @emph{late locking}, there is the chance that you can break
synchronization by editing a file as it is being read by the proof
assistant, and saving it before processing finishes.

In fact, there is a general problem of editing files which may be
processed by the proof assistant automatically.  Synchronization can be
broken whenever you have unsaved changes in a proof script buffer and
the proof assistant processes the corresponding file.  (Of course, this
problem is familiar from program development using separate editors
and compilers).  The good news is that Proof General can detect the
problem and flashes up a warning in the response buffer.  You can then
visit the modified buffer, save it and retract to the beginning. Then
you are back on track.



@c only true for LEGO!
@c If the proof assistant is not happy with the script and
@c complains with an error message, the buffer will still be marked as
@c having been completely processed. Sorry. You need to visit the
@c troublesome file, retract (which will always retract to the beginning of 
@c the file) and debug the problem e.g., by asserting all of the buffer
@c under the supervision of Proof General, see @ref{Script processing
@c commands}. 


@node Retracting across files
@section Retracting across files
@cindex Retraction

Make sure that the current script buffer has either been completely
asserted or retracted (Proof General enforces this).  Then you can
retract proof scripts in a different file. Simply visit a file that has
been processed earlier and retract in it, using the retraction commands
from @pxref{Script processing commands}. Apart from removing parts of the
locked region in this buffer, all files which depend on it will be
retracted (and thus unlocked) automatically. Proof General reminds you
that now is a good time to save any unmodified buffers.

@node Asserting across files
@section Asserting across files
@cindex Assertion

Make sure that the current script buffer has either been completely
asserted or retracted. Then you can assert proof scripts in a different
file. Simply visit a file that contains no locked region and assert some
command with the usual assertion commands, @pxref{Script processing
commands}. Proof General reminds you that now is a good time to save any
unmodified buffers.  This is particularly useful as assertion may cause
the proof assistant to automatically process other files.


@node Automatic multiple file handling
@section Automatic multiple file handling

To make it easier to adapt Proof General for a proof assistant, there is
another possibility for multiple file support --- that it is provided
automatically by Proof General and not integrated with the
file-management system of the proof assistant.

In this case, Proof General assumes that the only files processed are
the ones it has sent to the proof assistant itself.  Moreover, it
(conservatively) assumes that there is a linear dependency between files
in the order they were processed.

If you only have automatic multiple file handling, you'll find that any
files loaded directly by the proof assistant are @emph{not} locked when
you visit them in Proof General.  Moreover, if you retract a file it may
retract more than is strictly necessary (because it assumes a linear
dependency).

For further technical details of the ways multiple file scripting is
configured, see @i{Handling multiple files} in
the @i{Adapting Proof General} manual.



@node Escaping script management
@section Escaping script management
@cindex Shell

Occasionally you may want to review the dialogue of the entire session
with the proof assistant, or check that it hasn't done something
unexpected.  Experienced users may also want to directly communicate
with the proof assistant rather than sending commands via the
minibuffer, @pxref{Proof assistant commands}.

Although the proof shell is usually hidden from view, it is run in a
buffer which provides the usual full editing and history facilities of
Emacs shells (see the package @file{comint.el} distributed with your
version of Emacs). You can switch to it using the menu:

@lisp
  Proof-General -> Buffers -> Shell
@end lisp

@b{Warning:} you can probably cause confusion by typing in the shell
buffer!  Proof General may lose track of the state of the proof
assistant.  Output from the assistant is only fully monitored when Proof
General is in control of the shell.

When in control, Proof General watches the output from the proof
assistant to guess when a file is loaded or when a proof step is taken
or undone.  What happens when you type in the shell buffer directly
depends on how complete the communication is between Proof General and
the prover (which depends on the particular instantiation of Proof
General).

If synchronization is lost, you have two options to resynchronize. If
you are lucky, it might suffice to use the key:

@table @kbd
@item C-c C-z
@code{proof-frob-locked-end}
@end table

This command is disabled by default, to protect novices using it
accidently.

If @code{proof-frob-locked-end} does not work, you will need to restart
script management altogether (@pxref{Proof assistant commands}).

@c TEXI DOCSTRING MAGIC: proof-frob-locked-end
@deffn Command proof-frob-locked-end 
Move the end of the locked region backwards to regain synchronization.@*
Only for use by consenting adults.

This command can be used to repair synchronization in case something
goes wrong and you want to tell Proof General that the proof assistant
has processed less of your script than Proof General thinks.

You should only use it to move the locked region to the end of
a proof command.
@end deffn


@node Support for other Packages
@chapter Support for other Packages

Proof General makes some configuration for other Emacs packages which
provide various useful facilities that can make your editing
more effective.

Sometimes this configuration is purely at the proof assistant specific
level (and so not necessarily available), and sometimes it is made using
Proof General settings.

When adding support for a new proof assistant, we suggest that these
other packages are supported, as a convention.

The packages currently supported are 
@code{font-lock}, 
@code{x-symbol},
@code{func-menu},
@code{outline-mode},
@code{completion},
and @code{etags}.


@menu
* Syntax highlighting::         
* X-Symbol support::
* Support for function menus::  
* Support for outline mode::    
* Support for completion::            
* Support for tags::            
@end menu

@node Syntax highlighting
@section Syntax highlighting
@vindex lego-mode-hooks
@vindex coq-mode-hooks
@vindex isa-mode-hooks
@cindex font lock 
@cindex colour
@c Proof General specifics  

Proof script buffers are decorated (or @i{fontified}) with colours, bold
and italic fonts, etc, according to the syntax of the proof language and
the settings for @code{font-lock-keywords} made by the proof assistant
specific portion of Proof General.  Moreover, Proof General usually
decorates the output from the proof assistant, also using
@code{font-lock}.

In XEmacs, fontification is automatically turned on. To automatically
switch on fontification in GNU Emacs 20.4, you may need to engage
@code{M-x global-font-lock-mode}.  The old mechanism of adding hooks to
the mode hooks (@code{lego-mode-hooks}, @code{coq-mode-hooks}, etc) is
no longer recommended; it should not be needed in latest Emacs versions
which have more flexible customization.

Fontification for output is controlled by a separate switch in Proof
General. Set @code{proof-output-fontify-enable} to @code{nil} if you
don't want the output from your proof assistant to be fontified
according to the setting of @code{font-lock-keywords} in the proof
assistant specific portion of Proof General. @xref{User options}.

By the way, the choice of colour, font, etc, for each kind of markup is
fully customizable in Proof General.  Each @emph{face} (Emacs
terminology) controlled by its own customization setting.
You can display a list of all of them using the customize
menu: 
@lisp
Proof General -> Customize -> Faces -> Proof Faces.
@end lisp


@node X-Symbol support
@section X-Symbol support
@cindex real symbols
@cindex X-Symbols
@cindex Greek letters
@cindex logical symbols
@cindex mathematical symbols

The X-Symbol package displays characters from a variety of fonts in
Emacs buffers, automatically converting between codes for special
characters and @i{tokens} which are character sequences stored in files.

Proof General uses X-Symbol to allow interaction between the user and
the proof assistant to use tokens, yet appear to be using special
characters.  So proof scripts and proofs can be processed with real
mathematical symbols, Greek letters, etc.

You will be able to enable X-Symbol support if you have installed the
X-Symbol package and support has been provided in Proof General for a
token language for your proof assistant.
The X-Symbol package is available from
@uref{http://x-symbol.sourceforge.net/}.

Notice that for proper symbol support, the proof assistant needs to have
a special @i{token language}, or a special character set, to use
symbols.  In this case, the proof assistant will output, and accept as
input, tokens like @code{\longrightarrow}, which display as the
corresponding symbols.  However, for proof assistants which do not have
such token support, we can use "fake" symbol support quite effectively,
displaying ordinary character sequences such as @code{-->} with symbols.
The only problem with this hack is that it can cause surprising results,
when you really want character sequences instead of, for example, Greek
letters!

@c @xref{Configuring X-Symbol}, for notes about how to configure
@c a proof assistant to use X-Symbol in Proof General.


@node Support for function menus
@section Support for function menus
@vindex proof-goal-with-hole-regexp
@cindex func-menu
@cindex fume-func

The Emacs package @code{func-menu} (formerly called @code{fume-func}) is
a handy facility to make a menu from the names of entities declared in a
buffer.  Proof General configures @code{func-menu} so that you can
quickly jump to particular proofs in a script buffer.  (This is done
with the configuration variables @code{proof-goal-with-hole-regexp} and
@code{proof-save-with-hole-regexp}.)
@c , @pxref{Proof script mode} for further details.

If you want to use function menu, you can simply select "Function menu"
from the Proof General menu, or type @kbd{M-x function-menu}.

Although the package is distributed with XEmacs, it is not enabled by
default every time you visit a buffer.  To enable it by default
(i.e. avoid typing @code{M-x function-menu}), you should find the file
@file{func-menu.el} and follow the instructions there.

GNU Emacs 20.4 does not have the function menu library built in, but you
may be able to download it from the elisp archives.  A similar mode
which is supported is @code{imenu}, also in XEmacs.  Proof General would
be grateful if anyone can send patches for using @code{imenu}
as an alternative to function menu.


@node Support for outline mode
@section Support for outline mode
@cindex outline mode

Proof General configures Emacs variables (@code{outline-regexp} and
@code{outline-heading-end-regexp}) so that outline minor mode can be
used on proof script files.  The headings taken for outlining are the
"goal" statements at the start of goal-save sequences, 
@pxref{Goal-save sequences}. If you want to use @code{outline} to hide 
parts of the proof script in the @emph{locked} region, you need to disable
@code{proof-strict-read-only}.

Use @kbd{M-x outline-minor-mode} to turn on outline minor mode.
Functions for navigating, hiding, and revealing the proof script are
available in menus.

See @inforef{Outline Mode, ,(xemacs)} for more information about
outline mode.

@node Support for completion
@section Support for completion
@cindex completion

You might find the @emph{completion} facility of Emacs useful when
you're using Proof General.  The key @kbd{C-RET} is defined to invoke
the @code{complete} command.  Pressing @kbd{C-RET} cycles through
completions displaying hints in the minibuffer.

Completions are filled in according to what has been recently typed,
from a database of symbols.  The database is automatically saved at
the end of a session.

Proof General has the additional facility for setting a completion table
for each supported proof assistant, which gets loaded into the
completion database automatically.  Ideally the completion table would
be set from the running process according to the identifiers available
are within the particular context of a script file.  But until this is
available, this table may be set to contain a number of standard
identifiers available for your proof assistant.

The setting @code{@emph{PA}-completion-table} holds the list of
identifiers for a proof assistant.  The function
@code{proof-add-completions} adds these into the completion
database.

@c TEXI DOCSTRING MAGIC: PA-completion-table
@defvar PA-completion-table 
List of identifiers to use for completion for this proof assistant.@*
Completion is activated with C-return.

If this table is empty or needs adjusting, please make changes using
@samp{@code{customize-variable}} and send suggestions to proofgen@@dcs.ed.ac.uk.
@end defvar

The completion facility uses a library @file{completion.el} which
usually ships with XEmacs and GNU Emacs, and supplies the
@code{complete} function.

@c FIXME: edited from default.
@c NOT DOCSTRING MAGIC: complete
@deffn Command complete 
Fill out a completion of the word before point.  @*
Point is left at end.  Consecutive calls rotate through all possibilities.
Prefix args:
@table @kbd
@item C-u
leave point at the beginning of the completion, not the end.
@item a number
rotate through the possible completions by that amount
@item 0
same as -1 (insert previous completion)
@end table
See the comments at the top of @samp{completion.el} for more info.
@end deffn


@node Support for tags
@section Support for tags
@cindex tags

An Emacs "tags table" is a description of how a multi-file system is
broken up into files.  It lists the names of the component files and the
names and positions of the functions (or other named subunits) in each
file.  Grouping the related files makes it possible to search or replace
through all the files with one command.  Recording the function names
and positions makes possible the @kbd{M-.} command which finds the
definition of a function by looking up which of the files it is in.

Some instantiations of Proof General (currently LEGO and Coq) are
supplied with external programs (@file{legotags} and @file{coqtags}) for
making tags tables.  For example, invoking @samp{coqtags *.v} produces a
file @file{TAGS} for all files @samp{*.v} in the current
directory. Invoking @samp{coqtags `find . -name \*.v`} produces a file
@file{TAGS} for all files ending in @samp{.v} in the current directory
structure. Once a tag table has been made for your proof developments,
you can use the Emacs tags mechanisms to find tags, and complete symbols
from tags table.

One useful key-binding you might want to make is to set the usual
tags completion key @kbd{M-tab} to run @code{tag-complete-symbol} to use
completion from names in the tag table.  To set this binding in Proof
General script buffers, put this code in your @file{.emacs} file:
@lisp
(add-hook 'proof-mode-hook
  (lambda () (local-set-key '(meta tab) 'tag-complete-symbol)))
@end lisp
Since this key-binding interferes with a default binding that users may
already have customized (or may be taken by the window manager), Proof
General doesn't do this automatically.

Apart from completion, there are several other operations on tags.  One
common one is replacing identifiers across all files using
@code{tags-query-replace}.  For more information on how to use tags,
@inforef{Tags, ,(xemacs)}.

To use tags for completion at the same time as the completion mechanism
mentioned already, you can use the command @kbd{M-x add-completions-from-tags-table}.

@c TEXI DOCSTRING MAGIC: add-completions-from-tags-table


@deffn Command add-completions-from-tags-table 
Add completions from the current tags table.
@end deffn
@node Hints and Tips
@chapter Hints and Tips

Apart from the packages officially supported in Proof General, many.
many other features of Emacs are useful when using Proof General, even
though they need no specific configuration for Proof General.  It is
worth taking a bit of time to explore the Emacs manual to find out about
them.

Here we provide some hints and tips for a couple of Emacs features which
users have found valuable with Proof General.  Further contributions to
this chapter are welcomed!

@menu
* Using file variables::
* Using abbreviations::
@end menu


@node Using file variables
@section Using file variables
@cindex file variables

A very convenient way to customize file-specific variables is to use the
File Variables (@inforef{File Variables, ,xemacs}). This feature of
Emacs allows to specify the values to use for certain Emacs variables
when a file is loaded. Those values are written as a list at the end of
the file.

For example, in projects involving multiple directories, it is often
useful to set the variables @code{proof-prog-name} and
@code{compile-command} for each file. Here is an example for Coq users:
for the file @file{.../dir/bar/foo.v}, if you want Coq to be started
with the path @code{.../dir/theories/} added in the libraries path
(@code{"-I"} option), you can put at the end of @file{foo.v}:
@lisp

(* 
 Local Variables: 
 coq-prog-name: "coqtop -emacs -full -I ../theories"
 End:
*)
@end lisp

That way the good command is called when the scripting starts in
@file{foo.v}. Notice that the command argument @code{"-I ../theories"}
is specific to the file @file{foo.v}, and thus if you set it via the
configuration tool, you will need to do it each time you load this
file. On the contrary with this method, Emacs will do this operation
automatically when loading this file.

Extending the previous example, if the makefile for @file{foo.v} is
located in directory @file{.../dir/}, you can add the right compile
command:

@lisp
(* 
 Local Variables: 
 coq-prog-name: "coqtop -emacs -full -I ../theories"
 compile-command: "make -C .. -k bar/foo.vo" 
 End:
*)
@end lisp

And then the right call to make will be done if you use the @kbd{M-x
compile} command. Notice that the lines are commented in order to be
ignored by the proof assistant. It is possible to use this mechanism for
any other buffer local variable.  @inforef{File Variables,
,xemacs}.



@node Using abbreviations
@section Using abbreviations

A very useful package of Emacs supports automatic expansions of
abbreviations as you type, @inforef{Abbrevs, ,(xemacs)}.

Proof General has no special support for abbreviations, we just mention
it here to encourage its use.  For example, the proof assistant Coq has
many command strings that are long, such as ``Reflexivity,''
``Inductive,'' ``Definition'' and ``Discriminate.''  Here is the
Coq Proof General author's suggested abbreviations for Coq:
@lisp
"assn" 0 "Assumption"
"ax" 0 "Axiom"
"coern" 0 "Coercion"
"cofixpt" 0 "CoFixpt"
"coindv" 0 "CoInductive"
"constr" 0 "Constructor"
"contradn" 0 "Contradiction"
"defn" 0 "Definition"
"discr" 0 "Discriminate"
"extrn" 0 "Extraction"
"fixpt" 0 "Fixpoint"
"genz" 0 "Generalize"
"hypo" 0 "Hypothesis"
"immed" 0 "Immediate"
"indn" 0 "Induction"
"indv" 0 "Inductive"
"injn" 0 "Injection"
"intn" 0 "Intuition"
"invn" 0 "Inversion"
"pmtr" 0 "Parameter"
"refly" 0 "Reflexivity"
"rmk" 0 "Remark"
"specz" 0 "Specialize"
"symy" 0 "Symmetry"
"thm" 0 "Theorem"
"transpt" 0 "Transparent"
"transy" 0 "Transitivity"
"trivial" 0 "Trivial"
"varl" 0 "Variable"
@end lisp

The above list was taken from the file that Emacs saves between
sessions.  The easiest way to configure abbreviations is as you write,
by using the key presses @kbd{C-x a g} (@code{add-global-abbrev}) or
@kbd{C-x a i g} (@code{inverse-add-global-abbrev}).  To enable automatic
expansion of abbreviations (which can be annoying), the @code{Abbrev}
minor mode, type @kbd{M-x abbrev-mode RET}. When you are not in Abbrev
mode you can expand an abbreviation by pressing @kbd{C-x '}
(@code{expand-abbrev}). See the Emacs manual for more details.






@node Customizing Proof General
@chapter Customizing Proof General
@cindex Customization


There are two ways of customizing Proof General: it can be customized
for a user's preferences using a particular proof assistant, or it can
be customized by a developer to add support for a new proof assistant.
The latter kind of customization we call instantiation, or
@emph{adapting}. See the @i{Adapting Proof General} manual for how to do
this.  Here we cover the user-level customization for Proof General.

There are two kinds of user-level settings in Proof General: 
@itemize @bullet
@item Settings that apply @emph{globally} to all proof assistants.
@item those that can be adjusted for each proof assistant @emph{individually}.
@end itemize
The first sort have names beginning with @code{proof-}.  The second sort
have names which begin with a symbol corresponding to the proof
assistant: for example, @code{isa-}, @code{coq-}, etc.  The symbol is
the root of the mode name.  @xref{Quick start guide}, for a table of the
supported modes.  To stand for an arbitrary proof assistant, we write
@code{@emph{PA}-} for these names.

In this chapter we only consider the generic settings: ones which apply
to all proof assistants (globally or individually).  The support for a
particular proof assistant may provide extra individual customization
settings not available in other proof assistants.  See the chapters
covering each assistant for details of those settings.


@menu
* Basic options::
* How to customize::          
* Display customization::       
* User options::                
* Changing faces::              
* Tweaking configuration settings::  
@end menu

@node Basic options
@section Basic options

Proof General has some common options which you can toggle directly from
the menu:
@lisp
   Proof-General -> Options
@end lisp
The effect of changing one of these options will be seen immediately (or
in the next proof step).  The window-control options
on this menu are described shortly.  @xref{Display customization}.

To save the current settings, use the usual Emacs save options command,
for XEmacs on the menu:
@lisp
   Options -> Save Options
@end lisp
or @code{M-x customize-save-customized}.

The options on this sub-menu are also available in the complete user
customization options group for Proof General.  For this you need
to know a little bit about how to customize in Emacs.


@node How to customize
@section How to customize
@cindex Using Customize
@cindex Emacs customization library 

Proof General uses the Emacs customization library to provide a friendly
interface.  You can access all the customization settings for Proof
General via the menu:
@lisp
   Proof-General -> Customize
@end lisp

Using the customize facility is straightforward.  You can select the
setting to customize via the menus, or with @code{M-x
customize-variable}.  When you have selected a setting, you are shown a
buffer with its current value, and facility to edit it.  Once you have
edited it, you can use the special buttons @var{set}, @var{save} and
@var{done}.  You must use one of @var{set} or @var{save} to get any
effect.  The @var{save} button stores the setting in your @file{.emacs}
file.  In XEmacs, the menu item @code{Options -> Save Options} saves all
settings you have edited.

A technical note.  In the customize menus, the variable names mentioned
later in this chapter may be abbreviated --- the "@code{proof}-" or
similar prefixes are omitted.  Also, some of the option settings may
have more descriptive names (for example, @var{on} and @var{off}) than
the low-level lisp values (non-@code{nil}, @code{nil}) which are
mentioned in this chapter.  These features make customize rather more
friendly than raw lisp.

You can also access the customize settings for Proof General from
other (non-script) buffers.  In XEmacs, the menu path is:
@lisp
   Options -> Customize -> Emacs -> External -> Proof General
@end lisp
in XEmacs.  In GNU Emacs, use the menu:
@lisp
   Help -> Customize -> Top-level Customization Group
@end lisp
and select the @code{External} and then @code{Proof-General} groups.

The complete set of customization settings will only be available after
Proof General has been fully loaded.  Proof General is fully loaded when
you visit a script file for the first time, or if you type @kbd{M-x
load-library RET proof RET}.

For more help with customize, see @inforef{Easy Customization, ,xemacs}.



@node Display customization
@section Display customization
@cindex display customization
@cindex multiple windows
@cindex buffer display customization
@cindex frames
@cindex multiple frames
@cindex three-buffer interaction

By default, Proof General displays two buffers during scripting, in a
split window on the display.  One buffer is the script buffer.  The
other buffer is either the goals buffer (e.g. @code{*isabelle-goals*})
or the response buffer (@code{*isabelle-response*}).  Proof General
switches between these last two automatically.  

Proof General allows several ways to customize this default display
model.

If your screen is large enough, you may prefer to display all three of
the interaction buffers at once.  This is useful, for example, to see
output from the @code{proof-find-theorems} command at the same time as
the subgoal list.  Set the user option @code{proof-dont-switch-windows} to
make Proof General keep both the goals and response buffer displayed.

@c TEXI DOCSTRING MAGIC: proof-dont-switch-windows
@defopt proof-dont-switch-windows 
Whether response and goals buffers have dedicated windows.@*
If non-nil, Emacs windows displaying messages from the prover will not
be switchable to display other windows.

This option can help manage your display.

Setting this option triggers a three-buffer mode of interaction where
the goals buffer and response buffer are both displayed, rather than
the two-buffer mode where they are switched between.  It also prevents
Emacs automatically resizing windows between proof steps.  

If you use several frames (the same Emacs in several windows on the
screen), you can force a frame to stick to showing the goals or
response buffer.

For single frame use this option may be inconvenient for
experienced Emacs users.

The default value is @code{nil}.
@end defopt

Sometimes during script management, there is no response from the proof
assistant to some command.  In this case you might like the empty
response window to be hidden so you have more room to see the proof
script.  The setting @code{proof-delete-empty-windows} helps you do this.

@c TEXI DOCSTRING MAGIC: proof-delete-empty-windows
@defopt proof-delete-empty-windows 
If non-nil, automatically remove windows when they are cleaned.@*
For example, at the end of a proof the goals buffer window will
be cleared; if this flag is set it will automatically be removed.
If you want to fix the sizes of your windows you may want to set this
variable to @code{'nil'} to avoid windows being deleted automatically.
If you use multiple frames, only the windows in the currently
selected frame will be automatically deleted.

The default value is @code{nil}.
@end defopt
This option only has an effect when you have set
@code{proof-dont-switch-windows}.

If you are working on a machine with a window system, you can use Emacs
to manage several @i{frames} on the display, to keep the goals buffer
displayed in a fixed place on your screen and in a certain font, for
example.  A convenient way to do this is via the user option
@c TEXI DOCSTRING MAGIC: proof-multiple-frames-enable

@defopt proof-multiple-frames-enable 
Whether response and goals buffers have separate frames.@*
If non-nil, Emacs will make separate frames (screen windows) for
the goals and response buffers, by altering the Emacs variable
@samp{@code{special-display-regexps}}.

The default value is @code{nil}.
@end defopt
Multiple frames work best when @code{proof-delete-empty-windows} is off
and @code{proof-dont-switch-windows} is on.


@node User options
@section User options
@c Index entries for each option 'concept'
@cindex User options
@cindex Strict read-only
@cindex Query program name
@cindex Dedicated windows
@cindex Remote host
@cindex Toolbar follow mode
@cindex Toolbar disabling
@cindex Toolbar button enablers
@cindex Proof script indentation
@cindex Indentation
@cindex Remote shell
@cindex Running proof assistant remotely
@c @cindex formatting proof script

Here is the complete set of user options for Proof General, apart from
the three display options mentioned above.  

User options can be set via the customization system already mentioned,
via the old-fashioned @code{M-x edit-options} mechanism, or simply by
adding @code{setq}'s to your @file{.emacs} file.  The first approach is
strongly recommended.

Unless mentioned, all of these settings can be changed dynamically,
without needing to restart Emacs to see the effect.  But you must use
customize to be sure that Proof General reconfigures itself properly.

@c TEXI DOCSTRING MAGIC: proof-splash-enable
@defopt proof-splash-enable 
If non-nil, display a splash screen when Proof General is loaded.

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-electric-terminator-enable
@defopt proof-electric-terminator-enable 
If non-nil, use electric terminator mode.@*
If electric terminator mode is enabled, pressing a terminator will 
automatically issue @samp{@code{proof-assert-next-command}} for convenience,
to send the command straight to the proof process.  If the command
you want to send already has a terminator character, you don't
need to delete the terminator character first.  Just press the
terminator somewhere nearby.  Electric!

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-toolbar-enable
@defopt proof-toolbar-enable 
If non-nil, display Proof General toolbar for script buffers.@*
NB: the toolbar is only available with XEmacs and GNU Emacs>=21.

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: PA-x-symbol-enable
@defopt PA-x-symbol-enable 
Whether to use x-symbol in Proof General for this assistant.@*
If you activate this variable, whether or not you really get x-symbol
support depends on whether your proof assistant supports it and
whether X-Symbol is installed in your Emacs.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-output-fontify-enable
@defopt proof-output-fontify-enable 
Whether to fontify output from the proof assistant.@*
If non-nil, output from the proof assistant will be highlighted
in the goals and response buffers.
(This is providing @code{font-lock-keywords} have been set for the 
buffer modes).

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-strict-read-only
@defopt proof-strict-read-only 
Whether Proof General is strict about the read-only region in buffers.@*
If non-nil, an error is given when an attempt is made to edit the
read-only region.  If nil, Proof General is more relaxed (but may give
you a reprimand!).

If you change @code{proof-strict-read-only} during a session, you must 
use the "Restart" button (or M-x @code{proof-shell-restart}) before
you can see the effect in buffers.

The default value for @code{proof-strict-read-only} depends on which
version of Emacs you are using.  In GNU Emacs, strict read only is buggy
when it used in conjunction with font-lock, so it is disabled by default.

The default value is @code{strict}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-toolbar-use-button-enablers
@defopt proof-toolbar-use-button-enablers 
If non-nil, toolbars buttons may be enabled/disabled automatically.@*
Toolbar buttons can be automatically enabled/disabled according to
the context.  Set this variable to nil if you don't like this feature
or if you find it unreliable.

Notes: 
* Toolbar enablers are only available with XEmacs 21 and later.
* With this variable nil, buttons do nothing when they would
otherwise be disabled.
* If you change this variable it will only be noticed when you 
next start Proof General.
* The default value for XEmacs built for solaris is nil, because
of unreliabilities with enablers there.

The default value is @code{t}.
@end defopt

@c This one removed: proof-auto-retract

@c TEXI DOCSTRING MAGIC: proof-query-file-save-when-activating-scripting
@defopt proof-query-file-save-when-activating-scripting 
If non-nil, query user to save files when activating scripting.

Often, activating scripting or executing the first scripting command
of a proof script will cause the proof assistant to load some files
needed by the current proof script.  If this option is non-nil, the
user will be prompted to save some unsaved buffers in case any of 
them corresponds to a file which may be loaded by the proof assistant.

You can turn this option off if the save queries are annoying, but
be warned that with some proof assistants this may risk processing 
files which are out of date with respect to the loaded buffers!

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: PA-script-indent
@defopt PA-script-indent 
If non-nil, enable indentation code for proof scripts.

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-one-command-per-line
@defopt proof-one-command-per-line 
If non-nil, format for newlines after each proof command in a script.@*
This option is not fully-functional at the moment.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-prog-name-ask
@defopt proof-prog-name-ask 
If non-nil, query user which program to run for the inferior process.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-prog-name-guess
@defopt proof-prog-name-guess 
If non-nil, use @samp{@code{proof-guess-command-line}} to guess @code{proof-prog-name}.@*
This option is compatible with @code{proof-prog-name-ask}.
No effect if @code{proof-guess-command-line} is nil.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-tidy-response
@defopt proof-tidy-response 
Non-nil indicates that the response buffer should be cleared often.@*
The response buffer can be set either to accumulate output, or to
clear frequently.  

With this variable non-nil, the response buffer is kept tidy by
clearing it often, typically between successive commands (just like the
goals buffer).  

Otherwise the response buffer will accumulate output from the prover.

The default value is @code{t}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-show-debug-messages
@defopt proof-show-debug-messages 
Whether to display debugging messages in the response buffer.@*
If non-nil, debugging messages are displayed in the response giving
information about what Proof General is doing.
To avoid erasing the messages shortly after they're printed, 
you should set @samp{@code{proof-tidy-response}} to nil.

The default value is @code{nil}.
@end defopt


@c ******* NON-BOOLEANS *******

@c TEXI DOCSTRING MAGIC: proof-follow-mode
@defopt proof-follow-mode 
Choice of how point moves with script processing commands.@*
One of the symbols: @code{'locked}, @code{'follow}, @code{'ignore}.

If @code{'locked}, point sticks to the end of the locked region.
If @code{'follow}, point moves just when needed to display the locked region end.
If @code{'ignore}, point is never moved after movement commands or on errors.

If you choose @code{'ignore}, you can find the end of the locked using
@samp{M-x @code{proof-goto-end-of-locked}}.

The default value is @code{locked}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-auto-action-when-deactivating-scripting
@defopt proof-auto-action-when-deactivating-scripting 
If @code{'retract} or @code{'process}, do that when deactivating scripting.

With this option set to @code{'retract} or @code{'process}, when scripting 
is turned off in a partly processed buffer, the buffer will be 
retracted or processed automatically.

With this option unset (nil), the user is questioned instead.

Proof General insists that only one script buffer can be partly
processed: all others have to be completely processed or completely
unprocessed.  This is to make sure that handling of multiple files
makes sense within the proof assistant.

NB: A buffer is completely processed when all non-whitespace is
locked (coloured blue); a buffer is completely unprocessed when there
is no locked region.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-script-command-separator
@defopt proof-script-command-separator 
String separating commands in proof scripts.@*
For example, if a proof assistant prefers one command per line, then 
this string should be set to a newline.  Otherwise it should be
set to a space.

The default value is @code{" "}.
@end defopt

@c TEXI DOCSTRING MAGIC: proof-rsh-command
@defopt proof-rsh-command 
Shell command prefix to run a command on a remote host.  @*
For example,
@lisp
   ssh bigjobs
@end lisp
Would cause Proof General to issue the command @samp{ssh bigjobs isabelle}
to start Isabelle remotely on our large compute server called @samp{bigjobs}.

The protocol used should be configured so that no user interaction
(passwords, or whatever) is required to get going.

The default value is @code{""}.
@end defopt




@node Changing faces
@section Changing faces

The fonts and colours that Proof General uses are configurable.  If you
alter faces through the customize menus (or the command @kbd{M-x
customize-face}), only the particular kind of display in use (colour
window system, monochrome window system, console, @dots{}) will be
affected.  This means you can keep separate default settings for each
different display environment where you use Proof General.

As well as the faces listed below, Proof General may use the regular
@code{font-lock-} faces (eg @code{font-lock-keyword-face},
@code{font-lock-variable-name-face}, etc) for fontifying the proof
script or proof assistant output.  These can be altered to your taste
just as easily, but note that changes will affect all other modes
which use them!


@c TEXI DOCSTRING MAGIC: proof-queue-face
@deffn Face proof-queue-face 
Face for commands in proof script waiting to be processed.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-locked-face
@deffn Face proof-locked-face 
Face for locked region of proof script (processed commands).
@end deffn

@c TEXI DOCSTRING MAGIC: proof-error-face
@deffn Face proof-error-face 
Face for error messages from proof assistant.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-warning-face
@deffn Face proof-warning-face 
Face for warning messages.@*
Warning messages can come from proof assistant or from Proof General itself.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-debug-message-face
@deffn Face proof-debug-message-face 
Face for debugging messages from Proof General.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-declaration-name-face
@deffn Face proof-declaration-name-face 
Face for declaration names in proof scripts.@*
Exactly what uses this face depends on the proof assistant.
@end deffn


@c TEXI DOCSTRING MAGIC: proof-tacticals-name-face
@deffn Face proof-tacticals-name-face 
Face for names of tacticals in proof scripts.@*
Exactly what uses this face depends on the proof assistant.
@end deffn

@c TEXI DOCSTRING MAGIC: proof-eager-annotation-face
@deffn Face proof-eager-annotation-face 
Face for important messages from proof assistant.
@end deffn

@c Maybe this detail of explanation belongs in the internals,
@c with just a hint here.
The slightly bizarre name of the last face comes from the idea that
while large amounts of output are being sent from the prover, some
messages should be displayed to the user while the bulk of the output is
hidden.  The messages which are displayed may have a special annotation
to help Proof General recognize them, and this is an "eager" annotation
in the sense that it should be processed as soon as it is observed by
Proof General.




@node Tweaking configuration settings
@section Tweaking configuration settings

This section is a note for advanced users.

Configuration settings are the per-prover customizations of Proof
General.  These are not intended to be adjusted by the user.  But
occasionally you may like to test changes to these settings to improve
the way Proof General works.  You may want to do this when a proof
assistant has a flexible proof script language in which one can define
new tactics or even operations, and you want Proof General to recognize
some of these which the default settings don't mention.  So please feel
free to try adjusting the configuration settings and report to us if you
find better default values than the ones we have provided.

The configuration settings appear in the customization group
@code{prover-config}, or via the menu
@lisp
    Proof-General -> Internals ->  Prover Config
@end lisp

One basic example of a setting you may like to tweak is:

@c TEXI DOCSTRING MAGIC: proof-assistant-home-page
@defvar proof-assistant-home-page 
Web address for information on proof assistant.@*
Used for Proof General's help menu.
@end defvar

Most of the others are more complicated.  For more details of the
settings, see @i{Adapting Proof General} for full details.  To browse
the settings, you can look through the customization groups
@code{prover-config}, @code{proof-script} and @code{proof-shell}.  The
group @code{proof-script} contains the configuration variables for
scripting, and the group @code{proof-shell} contains those for
interacting with the proof assistant.

Unfortunately, although you can use the customization mechanism to set
and save these variables, saving them may have no practical effect
because the default settings are mostly hard-wired into the proof
assistant code.  Ones we expect may need changing appear as proof
assistant specific configurations.  For example,
@code{proof-assistant-home-page} is set in the LEGO code from the value
of the customization setting @code{lego-www-home-page}.  At present
there is no easy way to save changes to other configuration variables
across sessions, other than by editing the source code.  (In future
versions of Proof General, we plan to make all configuration
settings editable in Customize, by shadowing the settings as 
prover specific ones using the @code{@emph{PA}-} mechanism).
@c Please contact us if this proves to be a problem for any variable.




@c
@c  CHAPTER: LEGO Proof General
@c 
@node LEGO Proof General
@chapter LEGO Proof General
@cindex LEGO Proof General

LEGO proof script mode is a mode derived from proof script mode for
editing LEGO scripts. An important convention is that proof script
buffers @emph{must} start with a module declaration. If the proof script
buffer's file name is @file{fermat.l}, then it must commence with a
declaration of the form

@lisp
Module fermat;
@end lisp

If, in the development of the module @samp{fermat}, you require material
from other module e.g., @samp{lib_nat} and @samp{galois}, you need to
specify this dependency as part of the module declaration:

@lisp
Module fermat Import lib_nat galois;
@end lisp

No need to worry too much about efficiency. When you retract back to a
module declaration to add a new import item, LEGO does not actually
retract the previously imported modules. Therefore, reasserting the
extended module declaration really only processes the newly imported
modules.

Using the LEGO Proof General, you never ever need to use administrative
LEGO commands such as @samp{Forget}, @samp{ForgetMark}, @samp{KillRef},
@samp{Load}, @samp{Make}, @samp{Reload} and @samp{Undo} again
@footnote{And please, don't even think of including those in your LEGO
proof script!}. You can concentrate on your actual proof developments.
Script management in Proof General will invoke the appropriate commands
for you. Proving with LEGO has never been easier.

@menu
* LEGO specific commands::      
* LEGO tags::                   
* LEGO customizations::         
@end menu


@node LEGO specific commands
@section LEGO specific commands

In addition to the commands provided by the generic Proof General (as
discussed in the previous sections) the LEGO Proof General provides a
few extensions. In proof scripts, there are some abbreviations for
common commands:

@kindex C-c C-a C-i
@kindex C-c C-a C-I
@kindex C-c C-a C-R
@table @kbd
@item C-c C-a C-i   
intros
@item C-c C-a C-I   
Intros
@item C-c C-a C-R   
Refine
@end table

@node LEGO tags
@section LEGO tags

You
might want to ask your local system administrator to tag the directories
@file{lib_Prop}, @file{lib_Type} and @file{lib_TYPE} of the LEGO
library. See @ref{Support for tags}, for further details on tags.



@node LEGO customizations
@section LEGO customizations

We refer to chapter @ref{Customizing Proof General}, for an introduction
to the customisation mechanism. In addition to customizations at the
generic level, for LEGO you can also customize:

@c TEXI DOCSTRING MAGIC: lego-tags
@defopt lego-tags 
The directory of the @var{tags} table for the @var{lego} library

The default value is @code{"/usr/lib/lego/lib_Type/"}.
@end defopt

@c TEXI DOCSTRING MAGIC: lego-www-home-page
@defvar lego-www-home-page 
Lego home page URL.
@end defvar

@c We don't worry about the following for now. These are too obscure.
@c lego-indent
@c lego-test-all-name

@c We also don't document any of the internal variables which have been
@c set to configure the generic Proof General and which the user should
@c not tamper with


@node Coq Proof General
@chapter Coq Proof General

Coq Proof General is an instantiation of Proof General for the Coq proof
assistant.  It supports most of the generic features of Proof General,
but does not have integrated file management or proof-by-pointing yet.

@menu
* Coq-specific commands::
* Coq-specific variables::
* Editing multiple proofs::
* User-loaded tactics::
@end menu


@node Coq-specific commands
@section Coq-specific commands
@kindex C-c C-a C-i
@kindex C-c C-a C-a
@kindex C-c C-a C-s
@kindex C-c C-a C-e
@kindex C-c C-a C-o

Coq Proof General supplies the following key-bindings:
@table @kbd
@item C-c C-a C-i   
Inserts ``Intros '' 
@item C-c C-a C-a
Inserts ``Apply '' 
@item C-c C-a C-s
Inserts ``Section ''
@item C-c C-a C-e
Inserts ``End <section-name>.'' (this should work well with nested sections).
@item C-c C-a C-o
Prompts for a SearchIsos argument.
@end table

@node Coq-specific variables
@section Coq-specific variables
@kindex coq-version-is-V7

The variable
@lisp
  coq-version-is-V7
@end lisp
is used to force version of Coq, if it is t, then Coq is considered in
version 7, if it is nil, then Coq is considered in an old version
(V6). You should not have to set this variable, since ProofGeneral sets
it by doing the shell command:
@lisp
  (concat coq-prog-name "-v")
@end lisp

If you have problems with different versions of Coq, you can set this
variable in your config file (before ProofGeneral is loaded).

@node Editing multiple proofs
@section Editing multiple proofs

Coq allows the user to enter top-level commands while editing a proof
script.  For example, if the user realizes that the current proof will
fail without an additional axiom, he or she can add that axiom to the
system while in the middle of the proof.  Similarly, the user can
nest lemmas, beginning a new lemma while in the middle of an earlier
one, and as the lemmas are proved or their proofs aborted they are
popped off a stack.

Coq Proof General supports this feature of Coq.  Top-level commands
entered while in a proof are well backtracked. If new lemmas are
started, Coq Proof General lets the user work on the proof of the new
lemma, and when the lemma is finished it falls back to the previous
one.  This is supported to any nesting depth that Coq allows.

@b{Special note:} The old feature that moved nested proofs outside the
current proof is disabled.

@node User-loaded tactics
@section User-loaded tactics

Another feature that Coq allows is the extension of the grammar of the
proof assistant by new tactic commands.  This feature interacts with the
proof script management of Proof General, because Proof General needs to
know when a tactic is called that alters the proof state.  When the user
tries to retract across an extended tactic in a script, the algorithm
for calculating how far to undo has a default behavior that is not
always accurate: do "@code{Undo 1.}" when in proof mode, and "@code{Back
1.}"  when in toplevel mode.

Coq Proof General does not currently support dynamic tactic extension in
Coq, but provide a way to add tactic and command names in the
@file{.emacs} file. Four Configurable variables allows to register
personal new tactics and commands. Commands and Tactics are split into
backable (resp. undoable), i.e. which need "@code{Back}"
(resp. "@code{Undo}") to be backtracked, and not backable (resp. not
undoable).

We give an example of existing commands that fit each category.

@itemize @bullet

@item @code{coq-user-non-backable-commands}: example: "@code{Print}"

@item @code{coq-user-backable-commands}: example: "@code{Require}"

@item @code{coq-user-undoable-tactics}: example: "@code{Intro}"
 
@item @code{coq-user-non-undoable-tactics}: example: "@code{Idtac}"
@end itemize

This variables are regexp lists. See their documentations in emacs
(@code{C-h v coq-user...})  for details on how to set them in your .emacs
file.

Example:
@lisp
(setq coq-user-backable-commands 
      '("MyHint" "MyRequire" "Show\\-+Mydata"))
@end lisp


To re-synchronize by hand, the user can use @code{C-c C-v}.  For
example, if the user does @code{C-c C-u} to move the point back past an
unknown tactic T, he or she can type @code{C-c C-v} <tactic before
T>. This then undoes the backtrack command that Proof General sent
erroneously.





@c Sorry, there is currently very little specific documentation
@c written for Coq Proof General. If any Coq user would like to
@c contribute, please send a message to @code{proofgen@@dcs.ed.ac.uk}.

@c Type @kbd{C-h C-m} to get a list of all Coq specific commands and
@c browse the customize menus to find out what customization options
@c there are for Coq.



@c
@c  CHAPTER: Isabelle Proof General
@c

@node Isabelle Proof General
@chapter Isabelle Proof General
@cindex Isabelle Proof General

Isabelle Proof General supports all major generic features of Proof
General, including integration with Isabelle's theory loader for proper
automatic multiple file handling.  Only support for tags and
proof-by-pointing is missing.

It is very important to note that there are actually two different
versions of Isabelle Proof General: for ``classic'' Isabelle and for
Isabelle/Isar.  An old-style Isabelle theory typically consists of
@file{.thy} and correspondent @file{.ML} files, while Isabelle/Isar
theories usually have a new-style @file{.thy} only, which has a slightly
different syntax and may contain both definitions and proofs.

While Isabelle is able to manage both classic and Isar theories at the
same time (the theory loader determines the source format
automatically), Proof General does @b{not} admit to work on both kinds
of Isabelle source files at the same time!  Proof General treats
@code{isa} and @code{isar} as different instances; there is no way to
switch modes once Proof General has been started.

The classic version of Isabelle Proof General includes a mode for
editing theory files taken from David Aspinall's Isamode interface, see
@uref{http://www.proofgeneral.org/~isamode}.  Detailed documentation for
the theory file mode is included with @code{Isamode}, there are some
notes on the special functions available and customization settings
below.

Note that in ``classic'' Isabelle, @file{.thy} files contain definitions
and declarations for a theory, while @file{.ML} contain proof scripts.
So most of Proof General's functions only make sense in @file{.ML}
files, and there is no toolbar and only a short menu for @file{.thy} files.

In Isabelle/Isar, on the other hand, @file{.thy} files contain proofs as
well as definitions for theories, so scripting takes place there and you
see the usual toolbar and scripting functions of Proof General.

The default Emacs mode setup of Proof General prefers the newer
@code{isar} version over @code{isa}.  To load the ``classic'' Isabelle
mode, you can either make sure to visit a @file{.ML} before a 
@file{.thy} file, or set the environment variable
@code{PROOFGENERAL_ASSISTANTS=isa} before starting Emacs in order to
prevent loading of the Isabelle/Isar mode.  Another way of
selecting Isa is to put a special modeline like this:
@lisp
  (* -*- isa -*- *)
@end lisp
near the top of your Isabelle @file{.thy} files (or at least, the
first file you visit).  This Emacs feature overrides the default
choice of mode based on the file extension.

Isabelle provides yet another way to invoke Proof General, including
additional means to select either version.  The standard installation
of Isabelle also makes the @code{isar} version of Proof General its
default user interface: running plain @code{Isabelle} starts an Emacs
session with Isabelle/Isar Proof General; giving an option @code{-I
false} refers to the classic version instead.  The defaults may be
changed by editing the Isabelle settings, see the Isabelle
documentation for details.

@menu
* Classic Isabelle::
* Isabelle/Isar::
@end menu

@node Classic Isabelle
@section Classic Isabelle
@cindex Classic Isabelle

Proof General for classic Isabelle primarily manages @file{.ML} files
containing proof scripts.  There is a separate mode for editing
old-style @file{.thy} files, which supports batch mode only.

@menu
* ML files::
* Theory files::                
* General commands for Isabelle::
* Specific commands for Isabelle::  
* Isabelle customizations::     
@end menu

@node ML files
@subsection ML files
@cindex ML files (in Isabelle)
@cindex Isabelle proof scripts

In Isabelle, ML files are used to hold proof scripts, as well as
definitions of tactics, proof procedures, etc.  So ML files are the
normal domain of Proof General.  But there are some things to be wary
of.

Proof General does not understand full ML syntax, so ideally you should
only use Proof General's scripting commands on @file{.ML} files which
contain proof commands (no ML functions, structures, etc).

If you do use files with Proof General which declare functions,
structures, etc, you should be okay provided your code doesn't include
non top-level semi-colons (which will confuse Proof General's simplistic
parser), and provided all value declarations (and other non proof-steps)
occur outside proofs.  This is because within proofs, Proof General
considers every ML command to be a proof step which is undoable.

For example, do this:
@lisp
   structure S = struct
     val x = 3
     val y = 4
   end;
@end lisp
instead of this:
@lisp
   structure S = struct
     val x = 3;
     val y = 4;
   end
@end lisp
In the second case, just the first binding in the structure body will be
sent to Isabelle and Proof General will wait indefinitely.

And do this:
@lisp
    val intros1 = REPEAT (resolve_tac [impI,allI] 1);
    Goal "Q(x) --> (ALL x. P(x) --> P(x))";
    br impI 1;
    by intros1;
    ba 1;
    qed "mythm";
@end lisp
instead of this:
@lisp
    Goal "Q(x) --> (ALL x. P(x) --> P(x))";
    br impI 1;
    val intros1 = REPEAT (resolve_tac [impI,allI] 1);
    by intros1;
    ba 1;
    qed "mythm";
@end lisp
In the last case, when you undo, Proof General wrongly considers the
@code{val} declaration to be a proof step, and it will issue an
@code{undo} to Isabelle to undo it.  This leads to a loss of
synchronization.  To fix things when this happens, simply retract to
some point before the @code{Goal} command and rearrange your script.

Having ML as a top-level, Isabelle even lets you redefine the entire
proof command language, which will certainly confuse Proof General.
Stick to using the standard functions, tactics, and tacticals and there
should be no problems.  (In fact, there should be no problems provided
you don't use your own "goal" or "qed" forms, which Proof General
recognizes.  As the example above shows, Proof General makes no
attempt to recognize arbitrary tactic applications).


@node Theory files
@subsection Theory files
@cindex Theory files (in Isabelle)
@cindex ML files (in Isabelle)

As well as locking ML files, Isabelle Proof General locks theory files
when they are loaded.  Theory files are always completely locked or
completely unlocked, because they are processed atomically.

Proof General tries to load the theory file for a @file{.ML} file
automatically before you start scripting.  This relies on new support
especially for Proof General built into Isabelle99's theory loader.

However, because scripting cannot begin until the theory is loaded, and
it should not begin if an error occurs during loading the theory, Proof
General @strong{blocks} waiting for the theory loader to finish.  If you
have a theory file which takes a long time to load, you might want to
load it directly, from the @file{.thy} buffer.  Extra commands are
provided in theory mode for this:

@c FIXME: should say something about this:
@c This can cause confusion in the theory loader later,
@c especially with @code{update()}.  To be safe, try to use just the Proof
@c General interface, and report any repeatable problems to
@c @code{isabelle@dcs.ed.ac.uk}.

@c Compared to Isamode's theory editing mode, some of the functions and key
@c bindings for interacting with Isabelle have been removed, and two new
@c functions are available.  

The key @kbd{C-c C-b} (@code{isa-process-thy-file}) will cause Isabelle
to read the theory file being edited.  This causes the file and all its
children (both theory and ML files) to be read.  Any top-level ML file
associated with this theory file is @emph{not} read, in contrast
with the @code{use_thy} command of Isabelle.

The key @kbd{C-c C-u} (@code{isa-retract-thy-file}) will retract
(unlock) the theory file being edited.  This unlocks the file and all
its children (theory and ML files); no changes occur in Isabelle itself.

@c TEXI DOCSTRING MAGIC: isa-process-thy-file
@deffn Command isa-process-thy-file file
Process the theory file @var{file}.  If interactive, use @code{buffer-file-name}.
@end deffn

@c TEXI DOCSTRING MAGIC: isa-retract-thy-file
@deffn Command isa-retract-thy-file file
Retract the theory file @var{file}. If interactive, use @code{buffer-file-name}.@*
To prevent inconsistencies, scripting is deactivated before doing this. 
So if scripting is active in an ML file which is not completely processed, 
you will be asked to retract the file or process the remainder of it.
@end deffn


@node General commands for Isabelle
@subsection General commands for Isabelle

This section has some notes on the instantiation of the generic part of
Proof General for Isabelle.  (The generic part of Proof General applies
to all proof assistants supported, and is described in detail in the
rest of this manual).

@strong{Find theorems}.  This toolbar/menu command invokes a special
version of @code{thms_containing}.  To give several constants, separate
their names with commas.

@node Specific commands for Isabelle
@subsection Specific commands for Isabelle

This section mentions some commands which are added specifically
to the Isabelle Proof General instance.

@cindex Switching to theory files
@kindex C-c C-o

In Isabelle proof script mode, @kbd{C-c C-o} (@code{thy-find-other-file})
finds and switches to the associated theory file, that is, the file with
the same base name but extension @file{.thy} swapped for @file{.ML}.

The same function (and key-binding) switches back to an ML file from the
theory file.


@c TEXI DOCSTRING MAGIC: thy-find-other-file
@deffn Command thy-find-other-file &optional samewindow
Find associated .ML or .thy file.@*
Finds and switch to the associated ML file (when editing a theory file)
or theory file (when editing an ML file).  
If @var{samewindow} is non-nil (interactively, with an optional argument)
the other file replaces the one in the current window.
@end deffn




@node Isabelle customizations
@subsection Isabelle customizations

Here are some of the user options specific to Isabelle.  You can set
these as usual with the customization mechanism.

@c TEXI DOCSTRING MAGIC: isabelle-web-page
@defvar isabelle-web-page 
URL of web page for Isabelle.
@end defvar


@c @unnumberedsubsec Theory file editing customization

@c TEXI DOCSTRING MAGIC: thy-use-sml-mode
@defopt thy-use-sml-mode 
If non-nil, invoke @code{sml-mode} inside "ML" section of theory files.@*
This option is left-over from Isamode.  Really, it would be more
useful if the script editing mode of Proof General itself could be based 
on @code{sml-mode}, but at the moment there is no way to do this.

The default value is @code{nil}.
@end defopt

@c TEXI DOCSTRING MAGIC: thy-indent-level
@defopt thy-indent-level 
Indentation level for Isabelle theory files.  An integer.

The default value is @code{2}.
@end defopt

@c TEXI DOCSTRING MAGIC: thy-sections
@defvar thy-sections 
Names of theory file sections and their templates.@*
Each item in the list is a pair of a section name and a template.
A template is either a string to insert or a function. Useful functions are:
@lisp
  @code{thy-insert-header}, @code{thy-insert-class}, @code{thy-insert-default-sort},
  @code{thy-insert-const}, @code{thy-insert-rule}.
@end lisp
The nil template does nothing.
You can add extra sections to theory files by extending this variable.
@end defvar

@c TEXI DOCSTRING MAGIC: thy-template
@defvar thy-template 
Template for theory files.@*
Contains a default selection of sections in a traditional order.
You can use the following format characters:

@samp{%t} --- replaced by theory name.

@samp{%p} --- replaced by names of parents, separated by @samp{+} characters.
@end defvar

@c ideal for above:
@c @defopt thy-template
@c Template for theory files.
@c Contains a default selection of sections in a traditional order.
@c You can use the following format characters:
@c   @code{%t}  -- replaced by theory name
@c   @code{%p}  -- replaced by names of parents, separated by @code{+}'s
@c @end defopt


@node Isabelle/Isar
@section Isabelle/Isar
@cindex Isabelle/Isar

Proof General for Isabelle/Isar manages new-style @file{.thy} files,
which may contain both definitions and proofs (human readable proof
texts as well as traditional scripts following the Isar syntax).

The syntax of Isabelle/Isar input is technically simple, enabling Proof
General to provide reliable control over incremental execution of the
text.  Thus it is very hard to let Proof General lose synchronization
with the Isabelle/Isar process.  The caveats of @file{.ML} files
discussed for the classic Isabelle version (@pxref{Classic Isabelle}) do
@b{not} apply here.

@menu
* General commands for Isabelle/Isar::
* Specific commands for Isabelle/Isar::  
@end menu

@node General commands for Isabelle/Isar
@subsection General commands for Isabelle/Isar

@strong{Find theorems}.  This toolbar/menu command invokes
@code{thms_containing}.  Several term arguments may be given, separated
by white space as usual in Isar.

@node Specific commands for Isabelle/Isar
@subsection Specific commands for Isabelle/Isar
@kindex C-c C-a h A
@kindex C-c C-a h C
@kindex C-c C-a h S
@kindex C-c C-a h T
@kindex C-c C-a h a
@kindex C-c C-a h b
@kindex C-c C-a h c
@kindex C-c C-a h f
@kindex C-c C-a h i
@kindex C-c C-a h m
@kindex C-c C-a h o
@kindex C-c C-a h t

The Isabelle/Isar instance of Proof General supplies several specific
help key bindings; these functions are offered within the prover help
menu as well.

@table @kbd
@item C-c C-a h A
Shows available antiquotation commands and options.
@item C-c C-a h C
Shows the current Classical Reasoner context.
@item C-c C-a h S
Shows the current Simplifier context.
@item C-c C-a h T
Shows the current set of transitivity rules (for calculational reasoning).
@item C-c C-a h a
Shows attributes available in current theory context.
@item C-c C-a h b
Shows all local term bindings.
@item C-c C-a h c
Shows all named local contexts (cases).
@item C-c C-a h f
Shows all local facts.
@item C-c C-a h i
Shows inner syntax of the current theory context (for types and terms).
@item C-c C-a h m
Shows proof methods available in current theory context.
@item C-c C-a h o
Shows all available commands of Isabelle/Isar's outer syntax.
@item C-c C-a h t
Shows theorems stored in the current theory node.
@end table

@kindex C-c C-a b
@kindex C-c C-a u
@kindex C-c C-a l

The following shortcuts insert control sequences into the text,
modifying the appearance of individual symbols (single letters,
mathematical entities etc.); the X-Symbol package will provide immediate
visual feedback.

@table @kbd
@item C-c C-a b
Inserts "\<^bold>"
@item C-c C-a u
Inserts "\<^sup>"
@item C-c C-a l
Inserts "\<^sub>"
@end table

Command termination via `@code{;}' is an optional feature of Isar
syntax.  Neither Isabelle/Isar nor Proof General require semicolons to
do their job.  The following command allows to get rid of command
terminators in existing texts.

@c TEXI DOCSTRING MAGIC: isar-strip-terminators
@deffn Command isar-strip-terminators 
Remove explicit Isabelle/Isar command terminators @samp{;} from the buffer.
@end deffn



@c
@c  CHAPTER: HOL Proof General
@c

@node HOL Proof General
@chapter HOL Proof General
@cindex HOL Proof General

HOL Proof General is a "technology demonstration" of Proof General for
HOL98.  This means that only a basic instantiation has been provided,
and that it is not yet supported as a maintained instantiation of Proof
General.

HOL Proof General has basic script management support, with a little bit
of decoration of scripts and output.  It does not rely on a modified
version of HOL, so the pattern matching may be fragile in certain cases.
Support for multiple files deduces dependencies automatically, so there
is no interaction with the HOL make system yet.

See the @file{example.sml} file for a demonstration proof script
which works with Proof General.

Note that HOL proof scripts often use batch-oriented single step tactic
proofs, but Proof General does not (yet) offer an easy way to edit these
kind of proofs.  They will replay simply as a single step proof and you
will need to convert from the interactive to batch form as usual if you
wish to obtain batch proofs.  Also note that Proof General does not
contain an SML parser, so there can be problems if you write complex ML
in proof scripts. @xref{ML files}, for the same issue with Isabelle.

HOL Proof General may work with variants of HOL other than HOL98, but is
untested.  Probably a few of the settings would need to be changed in a
simple way, to cope with small differences in output between the
systems.  (Please let us know if you modify the HOL98 version for
another variant of HOL).

Hopefully somebody from the HOL community is willing to adopt HOL Proof
General and support and improve it.  Please volunteer!  It needn't be a
large or heavy committment.  



@c
@c
@c APPENDIX: Obtaining and Installing
@c
@c
@node Obtaining and Installing
@appendix Obtaining and Installing

Proof General has its own
@uref{http://www.proofgeneral.org,home page} hosted at
Edinburgh.  Visit this page for the latest news!

@menu
* Obtaining Proof General::     
* Installing Proof General from tarball::  
* Installing Proof General from RPM package::  
* Setting the names of binaries::
* Notes for syssies::           
@end menu


@node Obtaining Proof General
@section Obtaining Proof General

You can obtain Proof General from the URL
@example
@uref{http://www.proofgeneral.org}.
@end example

The distribution is available in three forms
@itemize @bullet
@item A source tarball, @*
@uref{http://www.proofgeneral.org/ProofGeneral-devel-latest.tar.gz}
@item A Linux RPM package (for any architecture), @*
@uref{http://www.proofgeneral.org/ProofGeneral-latest.noarch.rpm}
@item A developer's tarball, @*
@uref{http://www.proofgeneral.org/ProofGeneral-devel-latest.tar.gz}
@end itemize

Both the source tarball and the RPM package include the generic elisp
code, code for LEGO, Coq, and Isabelle, installation instructions
(reproduced below) and this documentation.  

The developer's tarball contains our full source tree, including all of
the elisp and documentation, along with our low-level list of things to
do, sources for the images, some make files used to generate the release
itself from our CVS repository, and some test files.  Developers
interested in accessing our CVS repository directly should contact
@code{proofgen@@dcs.ed.ac.uk}.

@c was Installing Proof General from @file{.tar.gz}
@node Installing Proof General from tarball
@section Installing Proof General from tarball

Copy the distribution to some directory @var{mydir}.
Unpack it there. For example:
@example
# cd @var{mydir}
# gunzip ProofGeneral-@var{version}.tar.gz
# tar -xpf ProofGeneral-@var{version}.tar
@end example
If you downloaded the version called @var{latest}, you'll find it
unpacks to a numeric version number.

Proof General will now be in some subdirectory of @var{mydir}.  The name
of the subdirectory will depend on the version number of Proof General.
For example, it might be @file{ProofGeneral-2.0}.  It's convenient to
link it to a fixed name:
@example
# ln -sf ProofGeneral-2.0 ProofGeneral
@end example
Now put this line in your @file{.emacs} file:
@lisp
    (load-file "@var{mydir}/ProofGeneral/generic/proof-site.el")
@end lisp

@node Installing Proof General from RPM package
@section Installing Proof General from RPM package

To install an RPM package you need to be root.  Then type
@example
# rpm -Uvh ProofGeneral-latest.noarch.rpm
@end example

Now add the line:
@lisp
   (load-file "/usr/share/emacs/ProofGeneral/generic/proof-site.el")
@end lisp
to your @file{.emacs} or the site-wide initialisation file
@file{site-start.el}.

@node Setting the names of binaries
@section Setting the names of binaries

The @code{load-file} command you have added will load @file{proof-site}
which sets the Emacs load path for Proof General and add auto-loads and
modes for the supported assistants.

The default names for proof assistant binaries may work on your system.
If not, you will need to set the appropriate variables.  The easiest way
to do this (and most other customization of Proof General) is via the
Customize mechanism, see the menu item:
@example
  Proof-General -> Customize -> @var{Name of Assistant} -> Prog Name
@end example
The Proof-General menu is available from script buffers after Proof
General is loaded.  To load it manually, type
@lisp
  M-x load-library RET proof RET
@end lisp

If you do not want to use customize, simply add a line like this:
@lisp
  (setq coq-prog-name "/usr/bin/coqtop -emacs")
@end lisp
to your @file{.emacs} file.



@node Notes for syssies
@section Notes for syssies

Here are some more notes for installing Proof General in more complex
ways.  Only attempt things in this section if you really understand what
you're doing.

@unnumberedsubsec Byte compilation

Compilation of the Emacs lisp files improves efficiency but can
sometimes cause compatibility problems, especially if you use more than
one version of Emacs with the same @code{.elc} files.  Furthermore, we
develop Proof General with source files so may miss problems with the
byte compiled versions.  If you discover problems using the
byte-compiled @code{.elc} files which aren't present using the source
@code{.el} files, please report them to us.

You can compile Proof General by typing @code{make} in the directory
where you installed it.  


@unnumberedsubsec Site-wide installation

If you are installing Proof General site-wide, you can put the
components in the standard directories of the filesystem if you prefer,
providing the variables in @file{proof-site.el} are adjusted
accordingly (see @i{Proof General site configuration} in
@i{Adapting Proof General} for more details).  Make sure that
the @file{generic/} and assistant-specific elisp files are kept in
subdirectories (@file{coq/}, @file{isa/}, @file{lego/}) of
@code{proof-home-directory} so that the autoload directory calculations
are correct.

To prevent every user needing to edit their own @file{.emacs} files, you
can put the @code{load-file} command to load @file{proof-site.el} into
@file{site-start.el} or similar.  Consult the Emacs documentation for more
details if you don't know where to find this file.

@unnumberedsubsec Removing support for unwanted provers

You cannot run more than one instance of Proof General at a time: so if
you're using Coq, visiting an @file{.ML} file will not load Isabelle
Proof General, and the buffer remains in fundamental mode.  If there are
some assistants supported that you never want to use, you can adjust the
variable @code{proof-assistants} in @file{proof-site.el} to remove the
extra autoloads.  This is advisable in case the extensions clash with
other Emacs modes, for example @code{sml-mode} for @file{.ML} files, or
Verilog mode for @file{.v} files.  

See @i{Proof General site configuration} in @i{Adapting Proof General},
for more details of how to adjust the @code{proof-assistants} setting.

A simple alternative is to delete the relevant directories from the PG
distribution.  For example, to remove support for Coq, delete
the @file{coq} directory in the Proof General home directory.


@c Via the Customize mechanism, see the menu:
@c @example
@c   Options -> Customize -> Emacs -> External -> Proof General
@c @end example
@c or, after loading Proof General, in a proof script buffer
@c @example
@c   Proof-General -> Customize
@c @end example



@c
@c
@c APPENDIX: Known bugs and workarounds
@c
@c
@node Known bugs and workarounds
@appendix Known bugs and workarounds

This appendix has been removed!

Please consult the file
@uref{http://www.proofgeneral.org/ProofGeneral/BUGS,@file{BUGS}} in the
distribution for an up-to-date description bugs and other issues.

If you discover a problem which isn't mentioned in @file{BUGS}, please
let us know by sending a note to @code{proofgen@@dcs.ed.ac.uk}.

@node References
@unnumbered References

A short overview of the Proof General system is described in the
note:
@itemize @bullet
@item @b{[Asp00]}
David Aspinall.
@i{Proof General: A Generic Tool for Proof Development}.
Tools and Algorithms for the Construction and 
Analysis of Systems, Proc TACAS 2000.  LNCS 1785.
@end itemize

Script management as used in Proof General is described in the paper:

@itemize @bullet
@item @b{[BT98]}
Yves Bertot and Laurent Th@'ery. @i{A generic approach to building
user interfaces for theorem provers}. Journal of
Symbolic Computation, 25(7), pp. 161-194, February 1998.
@end itemize

Proof General has support for proof by pointing, as described in the
document:

@itemize @bullet
@item @b{[BKS97]}
Yves Bertot, Thomas Kleymann-Schreiber and Dilip Sequeira. @i{Implementing
Proof by Pointing without a
Structure Editor}. LFCS Technical Report ECS-LFCS-97-368. Also published as Rapport de recherche de
l'INRIA Sophia Antipolis RR-3286 
@end itemize




@node Function Index
@unnumbered Function and Command Index
@printindex fn

@node Variable Index
@unnumbered Variable and User Option Index
@printindex vr

@node Keystroke Index
@unnumbered Keystroke Index
@printindex ky

@node Concept Index
@unnumbered Concept Index
@printindex cp

@page
@contents
@bye