From b976aa1e49579b7b50cfb140cbac8cb6f4c881a7 Mon Sep 17 00:00:00 2001 From: Hugo Herbelin Date: Sun, 17 Jul 2016 09:28:56 +0200 Subject: More examples of recursive notations, with emphasis in reference manual. Further work would include: - Identify binders up to alpha-conversion (see #4932 with a list of binders of length at least 2, or #4592 on printing notations such as ex2). A cool example that one could also consider supporting: - Notation "[[ a , .. , b | .. | a , .. , b ]]" := (cons (cons a .. (cons b nil) ..) .. (cons a .. (cons b nil) ..) ..). --- doc/refman/RefMan-syn.tex | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'doc') diff --git a/doc/refman/RefMan-syn.tex b/doc/refman/RefMan-syn.tex index e91480ded3..92107b750b 100644 --- a/doc/refman/RefMan-syn.tex +++ b/doc/refman/RefMan-syn.tex @@ -589,6 +589,14 @@ Notation "[| t * ( x , y , .. , z ) ; ( a , b , .. , c ) * u |]" := (t at level 39). \end{coq_example*} +Recursive patterns can occur several times on the right-hand side. +Here is an example: + +\begin{coq_example*} +Notation "[> a , .. , b <]" := + (cons a .. (cons b nil) .., cons b .. (cons a nil) ..). +\end{coq_example*} + Notations with recursive patterns can be reserved like standard notations, they can also be declared within interpretation scopes (see section \ref{scopes}). @@ -634,7 +642,16 @@ empty. Here is an example of recursive notation with closed binders: \begin{coq_example*} Notation "'mylet' f x .. y := t 'in' u":= (let f := fun x => .. (fun y => t) .. in u) - (x closed binder, y closed binder, at level 200, right associativity). + (at level 200, x closed binder, y closed binder, right associativity). +\end{coq_example*} + +A recursive pattern for binders can be used in position of a recursive +pattern for terms. Here is an example: + +\begin{coq_example*} +Notation ``'FUNAPP' x .. y , f'' := + (fun x => .. (fun y => (.. (f x) ..) y ) ..) + (at level 200, x binder, y binder, right associativity). \end{coq_example*} \subsection{Summary} -- cgit v1.2.3