update in delayed_updating

[helm.git] / matita / matita / contribs / lambdadelta / delayed_updating / reduction / dfr.ma

diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
index ed077ae2cc772df22b7227dab1750ace5c243afd..5b5036593713ac1c84f09b2b7b6649f3aebd834a 100644 (file)
--- a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
+++ b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
@@ -16,15 +16,17 @@ include "delayed_updating/syntax/path_depth.ma".
 include "delayed_updating/syntax/path_structure.ma".
 include "delayed_updating/syntax/path_balanced.ma".
 include "delayed_updating/syntax/prototerm_constructors.ma".
+include "delayed_updating/syntax/prototerm_equivalence.ma".
 include "delayed_updating/substitution/fsubst.ma".
 include "delayed_updating/notation/relations/black_rightarrow_df_4.ma".
 
 (* DELAYED FOCUSED REDUCTION ************************************************)
 
-inductive dfr (p) (q) (t): predicate prototerm ≝
-| dfr_beta (b):
-  let r ≝ p●𝗔◗b●𝗟◗q in
-  r◖𝗱(↑❘q❘) ϵ t → ⊓(⊗b) → dfr p q t (t[⋔r←𝛗(↑❘q❘).t⋔(p◖𝗦)])
+definition dfr (p) (q): relation2 prototerm prototerm ≝
+           λt1,t2. ∃b.
+           let r ≝ p●𝗔◗b●𝗟◗q in
+           ∧∧ ⊓(⊗b) & r◖𝗱(↑❘q❘) ϵ t1 &
+              t2 ⇔ t1[⋔r←𝛗(↑❘q❘).t1⋔(p◖𝗦)]
 .
 
 interpretation