X-Git-Url: http://matita.cs.unibo.it/gitweb/?p=helm.git;a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fsyntax%2Fappend_length.ma;h=e7c79ebeeb2627e513618ca3dab1c9c992a2bd3e;hp=c1133e8c0fba47afcb25f4ce04f0180c58b3158d;hb=5c186c72f508da0849058afeecc6877cd9ed6303;hpb=282511a928532676813d99d08594cd5f98fcb80e

diff --git a/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma b/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma
index c1133e8c0..e7c79ebee 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma
@@ -103,9 +103,9 @@ qed-.
 
 (* Basic_1: was: c_tail_ind *)
 (* Basic_2A1: was: lenv_ind_alt *) 
-lemma lenv_ind_tail: ∀R:predicate lenv.
-                     R (⋆) → (∀I,L. R L → R (ⓘ{I}.L)) → ∀L. R L.
-#R #IH1 #IH2 #L @(f_ind … length … L) -L #x #IHx * //
+lemma lenv_ind_tail: ∀Q:predicate lenv.
+                     Q (⋆) → (∀I,L. Q L → Q (ⓘ{I}.L)) → ∀L. Q L.
+#Q #IH1 #IH2 #L @(f_ind … length … L) -L #x #IHx * //
 #L #I -IH1 #H destruct
 elim (lenv_case_tail … L) [2: * #K #J ]
 #H destruct /3 width=1 by/