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-rw-r--r--doc/sphinx/addendum/implicit-coercions.rst2
-rw-r--r--doc/sphinx/addendum/sprop.rst45
-rw-r--r--doc/sphinx/addendum/type-classes.rst6
3 files changed, 30 insertions, 23 deletions
diff --git a/doc/sphinx/addendum/implicit-coercions.rst b/doc/sphinx/addendum/implicit-coercions.rst
index cfaa681d20..a6dc15da55 100644
--- a/doc/sphinx/addendum/implicit-coercions.rst
+++ b/doc/sphinx/addendum/implicit-coercions.rst
@@ -37,6 +37,8 @@ In addition to these user-defined classes, we have two built-in classes:
* ``Funclass``, the class of functions; its objects are all the terms with a functional
type, i.e. of form :g:`forall x:A,B`.
+Formally, the syntax of classes is defined as:
+
.. insertprodn class class
.. prodn::
diff --git a/doc/sphinx/addendum/sprop.rst b/doc/sphinx/addendum/sprop.rst
index b2d3687780..b19239ed22 100644
--- a/doc/sphinx/addendum/sprop.rst
+++ b/doc/sphinx/addendum/sprop.rst
@@ -7,27 +7,26 @@ SProp (proof irrelevant propositions)
The status of strict propositions is experimental.
+ In particular, conversion checking through bytecode or native code
+ compilation currently does not understand proof irrelevance.
+
This section describes the extension of |Coq| with definitionally
proof irrelevant propositions (types in the sort :math:`\SProp`, also
known as strict propositions) as described in
:cite:`Gilbert:POPL2019`.
-Using :math:`\SProp` may be prevented by passing ``-disallow-sprop``
-to the |Coq| program or using :flag:`Allow StrictProp`.
+Use of |SProp| may be disabled by passing ``-disallow-sprop`` to the
+|Coq| program or by turning the :flag:`Allow StrictProp` flag off.
.. flag:: Allow StrictProp
:name: Allow StrictProp
- Allows using :math:`\SProp` when set and forbids it when unset. The
- initial value depends on whether you used the command line
- ``-disallow-sprop`` and ``-allow-sprop``.
-
-.. exn:: SProp not allowed, you need to Set Allow StrictProp or to use the -allow-sprop command-line-flag.
- :undocumented:
-
-.. coqtop:: none
+ Enables or disables the use of |SProp|. It is enabled by default.
+ The command-line flag ``-disallow-sprop`` disables |SProp| at
+ startup.
- Set Allow StrictProp.
+ .. exn:: SProp is disallowed because the "Allow StrictProp" flag is off.
+ :undocumented:
Some of the definitions described in this document are available
through ``Coq.Logic.StrictProp``, which see.
@@ -38,29 +37,35 @@ Basic constructs
The purpose of :math:`\SProp` is to provide types where all elements
are convertible:
-.. coqdoc::
+.. coqtop:: all
- Definition irrelevance (A:SProp) (P:A -> Prop) (x:A) (v:P x) (y:A) : P y := v.
+ Theorem irrelevance (A : SProp) (P : A -> Prop) : forall x : A, P x -> forall y : A, P y.
+ Proof.
+ intros * Hx *.
+ exact Hx.
+ Qed.
Since we have definitional :ref:`eta-expansion` for
functions, the property of being a type of definitionally irrelevant
values is impredicative, and so is :math:`\SProp`:
-.. coqdoc::
+.. coqtop:: all
Check fun (A:Type) (B:A -> SProp) => (forall x:A, B x) : SProp.
-.. warning::
-
- Conversion checking through bytecode or native code compilation
- currently does not understand proof irrelevance.
-
In order to keep conversion tractable, cumulativity for :math:`\SProp`
-is forbidden:
+is forbidden, unless the :flag:`Cumulative StrictProp` flag is turned
+on:
.. coqtop:: all
Fail Check (fun (A:SProp) => A : Type).
+ Set Cumulative StrictProp.
+ Check (fun (A:SProp) => A : Type).
+
+.. coqtop:: none
+
+ Unset Cumulative StrictProp.
We can explicitly lift strict propositions into the relevant world by
using a wrapping inductive type. The inductive stops definitional
diff --git a/doc/sphinx/addendum/type-classes.rst b/doc/sphinx/addendum/type-classes.rst
index bd4c276571..903aa266e2 100644
--- a/doc/sphinx/addendum/type-classes.rst
+++ b/doc/sphinx/addendum/type-classes.rst
@@ -241,7 +241,7 @@ binders. For example:
Definition lt `{eqa : EqDec A, ! Ord eqa} (x y : A) := andb (le x y) (neqb x y).
-The ``!`` modifier switches the way a binder is parsed back to the regular
+The ``!`` modifier switches the way a binder is parsed back to the usual
interpretation of Coq. In particular, it uses the implicit arguments
mechanism if available, as shown in the example.
@@ -323,7 +323,7 @@ Summary of the commands
.. cmdv:: Existing Class @ident
- This variant declares a class a posteriori from a constant or
+ This variant declares a class from a previously declared constant or
inductive definition. No methods or instances are defined.
.. warn:: @ident is already declared as a typeclass
@@ -394,7 +394,7 @@ few other commands related to typeclasses.
:name: typeclasses eauto
This proof search tactic implements the resolution engine that is run
- implicitly during type-checking. This tactic uses a different resolution
+ implicitly during type checking. This tactic uses a different resolution
engine than :tacn:`eauto` and :tacn:`auto`. The main differences are the
following: