X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=weblib%2Fbasics%2Flist2.ma;h=5d9929fc0e89dd6c3424605e25ba4881eb3a34ad;hb=50a9ed8c6207145fccf59e6a5dbbff935cd2c6d7;hp=2543b3084a52c09fae87853bc54fb96f6c36a446;hpb=b8a719bbb47d12e0a6b2c8cb2e5e26a2bf360be1;p=helm.git diff --git a/weblib/basics/list2.ma b/weblib/basics/list2.ma index 2543b3084..5d9929fc0 100644 --- a/weblib/basics/list2.ma +++ b/weblib/basics/list2.ma @@ -15,7 +15,7 @@ include "basics/list.ma". include "arithmetics/nat.ma". -let rec length (A:Type[0]) (l:a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a A) on l ≝ +img class="anchor" src="icons/tick.png" id="length"let rec length (A:Type[0]) (l:a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a A) on l ≝ match l with [ nil ⇒ a title="natural number" href="cic:/fakeuri.def(1)"0/a | cons a tl ⇒ a href="cic:/matita/arithmetics/nat/nat.con(0,2,0)"S/a (length A tl)]. @@ -23,7 +23,7 @@ let rec length (A:Type[0]) (l:a href="cic:/matita/basics/list/list.ind(1,0,1)" notation "|M|" non associative with precedence 60 for @{'norm $M}. interpretation "norm" 'norm l = (length ? l). -let rec nth n (A:Type[0]) (l:a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a A) (d:A) ≝ +img class="anchor" src="icons/tick.png" id="nth"let rec nth n (A:Type[0]) (l:a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a A) (d:A) ≝ match n with [O ⇒ a href="cic:/matita/basics/list/hd.def(1)"hd/a A l d - |S m ⇒ nth m A (a href="cic:/matita/basics/list/tail.def(1)"tail/a A l) d]. + |S m ⇒ nth m A (a href="cic:/matita/basics/list/tail.def(1)"tail/a A l) d]. \ No newline at end of file