diff options
| author |  pboutill <pboutill@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2012-12-21 21:47:43 +0000 |
|---|---|---|
| committer | pboutill <pboutill@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2012-12-21 21:47:43 +0000 |
| commit | ec8332223b1f6716e49bbf78e0489881ca7bfa2b (patch) | |
| tree | 95c23e65916507f8442e3d5f1ac11e675fca52b8 /theories/PArith | |
| parent | e9428d3127ca159451437c2abbc6306e0c31f513 (diff) | |
nat_iter n f x -> nat_rect _ x (fun _ => f) n
It is much beter for everything (includind guard condition and simpl refolding)
excepts typeclasse inference because unification does not recognize
(fun x => f x b) a when it sees f a b ...
git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@16112 85f007b7-540e-0410-9357-904b9bb8a0f7
Diffstat (limited to 'theories/PArith')
| -rw-r--r-- | theories/PArith/BinPosDef.v | 4 | ||||
| -rw-r--r-- | theories/PArith/Pnat.v | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/theories/PArith/BinPosDef.v b/theories/PArith/BinPosDef.v index 4beeea31d..6d85f0723 100644 --- a/theories/PArith/BinPosDef.v +++ b/theories/PArith/BinPosDef.v @@ -484,8 +484,8 @@ Fixpoint lxor (p q:positive) : N := (** Shifts. NB: right shift of 1 stays at 1. *) -Definition shiftl_nat (p:positive)(n:nat) := nat_iter n xO p. -Definition shiftr_nat (p:positive)(n:nat) := nat_iter n div2 p. +Definition shiftl_nat (p:positive)(n:nat) := nat_rect _ p (fun _ => xO) n. +Definition shiftr_nat (p:positive)(n:nat) := nat_rect _ p (fun _ => div2) n. Definition shiftl (p:positive)(n:N) := match n with diff --git a/theories/PArith/Pnat.v b/theories/PArith/Pnat.v index 31e88a403..33505ccb3 100644 --- a/theories/PArith/Pnat.v +++ b/theories/PArith/Pnat.v @@ -192,7 +192,7 @@ Qed. Theorem inj_iter : forall p {A} (f:A->A) (x:A), - Pos.iter p f x = nat_iter (to_nat p) f x. + Pos.iter p f x = nat_rect (fun _ => A) x (fun _ => f) (to_nat p). Proof. induction p using peano_ind. trivial. intros. rewrite inj_succ, iter_succ. simpl. now f_equal. |