- we enabled a notation for ex2

[helm.git] / matita / matita / contribs / lambda / term.ma

diff --git a/matita/matita/contribs/lambda/term.ma b/matita/matita/contribs/lambda/term.ma
index 8c688dc8e9b10f874836791a38f5edfc36e64878..660830d2784222dac9bc681e15b5d144aaf24edc 100644 (file)
--- a/matita/matita/contribs/lambda/term.ma
+++ b/matita/matita/contribs/lambda/term.ma
@@ -47,3 +47,11 @@ notation "hvbox( 𝛌  . term 46 A )"
 notation "hvbox( @ term 46 C . break term 46 A )"
    non associative with precedence 46
    for @{ 'Application $C $A }.
+
+definition appl_compatible_dx: predicate (relation term) ≝ λR.
+                               ∀B,A1,A2. R A1 A2 → R (@B.A1) (@B.A2).
+
+lemma star_appl_compatible_dx: ∀R. appl_compatible_dx R →
+                               appl_compatible_dx (star … R).
+#R #HR #B #A1 #A2 #H elim H -A2 // /3 width=3/
+qed.