X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=weblib%2Fbasics%2Flist.ma;h=e699b626a4f2f02dab5c38a939871afab0a988c4;hb=c57538d8f84e2e2d73bbda4b07570c10b1bf32a3;hp=245a9fd3b4789818833887095b8db4cb1e04a1cf;hpb=f5b55b3e3395ec39a1429468ae833dbff72158c4;p=helm.git diff --git a/weblib/basics/list.ma b/weblib/basics/list.ma index 245a9fd3b..e699b626a 100644 --- a/weblib/basics/list.ma +++ b/weblib/basics/list.ma @@ -104,7 +104,7 @@ definition filter ≝ a href="cic:/matita/basics/list/foldr.fix(0,4,1)"foldr/a T (a href="cic:/matita/basics/list/list.ind(1,0,1)"list/a T) (λx,l0.if (p x) then (xa title="cons" href="cic:/fakeuri.def(1)":/a:l0) else l0) (a href="cic:/matita/basics/list/list.con(0,1,1)"nil/a T). definition compose ≝ λA,B,C.λf:A→B→C.λl1,l2. - a href="cic:/matita/basics/list/foldr.fix(0,4,1)"foldr/a ?? (λi,acc.(a href="cic:/matita/basics/list/map.fix(0,3,1)"map/a ?? (f i) l2)a title="append" href="cic:/fakeuri.def(1)"@/aacc) a title="nil" href="cic:/fakeuri.def(1)"[/a ] l1. + a href="cic:/matita/basics/list/foldr.fix(0,4,1)"foldr/a ?? (λi,acc.(a href="cic:/matita/basics/list/map.fix(0,3,1)"map/a ?? (f i) l2)a title="append" href="cic:/fakeuri.def(1)"@/aacc) a title="nil" href="cic:/fakeuri.def(1)"[/a ] l1. lemma filter_true : ∀A,l,a,p. p a a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a a href="cic:/matita/basics/bool/bool.con(0,1,0)"true/a → a href="cic:/matita/basics/list/filter.def(2)"filter/a A p (aa title="cons" href="cic:/fakeuri.def(1)":/a:l) a title="leibnitz's equality" href="cic:/fakeuri.def(1)"=/a a a title="cons" href="cic:/fakeuri.def(1)":/a: a href="cic:/matita/basics/list/filter.def(2)"filter/a A p l.