From b341c644ed7ad52779b148e7ba6e3dd9158c2174 Mon Sep 17 00:00:00 2001 From: herbelin Date: Sat, 16 Jul 2011 20:35:17 +0000 Subject: Tentative abbreviation "rew Heq in H" for eq_rect. (feedback welcome) git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@14281 85f007b7-540e-0410-9357-904b9bb8a0f7 --- theories/Vectors/VectorDef.v | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'theories/Vectors') diff --git a/theories/Vectors/VectorDef.v b/theories/Vectors/VectorDef.v index 777e68b45..adc2c09a3 100644 --- a/theories/Vectors/VectorDef.v +++ b/theories/Vectors/VectorDef.v @@ -197,18 +197,18 @@ Fixpoint rev_append_tail {A n p} (v : t A n) (w: t A p) | a :: v' => rev_append_tail v' (a :: w) end. +Import EqdepFacts. + (** This one has a better type *) Definition rev_append {A n p} (v: t A n) (w: t A p) :t A (n + p) := -eq_rect _ (fun n => t A n) (rev_append_tail v w) _ - (eq_sym _ _ _ (plus_tail_plus n p)). + rew <- (plus_tail_plus n p) in (rev_append_tail v w). (** rev [a₁ ; a₂ ; .. ; an] is [an ; a{n-1} ; .. ; a₁] Caution : There is a lot of rewrite garbage in this definition *) Definition rev {A n} (v : t A n) : t A n := - eq_rect _ (fun n => t A n) (rev_append v []) - _ (eq_sym _ _ _ (plus_n_O _)). + rew <- (plus_n_O _) in (rev_append v []). End BASES. Local Notation "v [@ p ]" := (nth v p) (at level 1). -- cgit v1.2.3