update in delayed_updating and ground

[helm.git] / matita / matita / contribs / lambdadelta / ground / relocation / xap.ma

diff --git a/matita/matita/contribs/lambdadelta/ground/relocation/xap.ma b/matita/matita/contribs/lambdadelta/ground/relocation/xap.ma
index 0f367b218935fe30bb24078908b49b3e678c10d5..0835ec53f5326d518fb4194b861542bc5312c70e 100644 (file)
--- a/matita/matita/contribs/lambdadelta/ground/relocation/xap.ma
+++ b/matita/matita/contribs/lambdadelta/ground/relocation/xap.ma
@@ -82,3 +82,9 @@ lemma tr_nap_plus (f) (m) (n):
       ⇂*[↑n]f＠❨m❩+f＠§❨n❩ = f＠§❨m+n❩.
 /2 width=1 by eq_inv_nsucc_bi/
 qed.
+
+lemma tr_xap_pos (f) (n):
+      n = ↑↓n → f＠❨n❩=↑↓(f＠❨n❩).
+#f #n #H0 >H0 -H0
+<tr_xap_ninj <nsucc_pnpred //
+qed.