X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fdelayed_updating%2Freduction%2Fdfr.ma;h=193136433188b5857954573034cac434610a108e;hb=3bf7a0b4185dbffe5b822c907956acdbe2d1c559;hp=3dca53142fb3a3e6fabc1d31a0fd34f1795831d1;hpb=f83215ca9b8d0019c85a991ec90c6c658c0aaff8;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
index 3dca53142..193136433 100644
--- a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
+++ b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
@@ -12,20 +12,23 @@
 (*                                                                        *)
 (**************************************************************************)
 
-include "delayed_updating/syntax/path_depth.ma".
-include "delayed_updating/syntax/path_structure.ma".
-include "delayed_updating/syntax/path_balanced.ma".
 include "delayed_updating/substitution/fsubst.ma".
+include "delayed_updating/syntax/prototerm_constructors.ma".
+include "delayed_updating/syntax/prototerm_eq.ma".
+include "delayed_updating/syntax/path_head.ma".
+include "delayed_updating/syntax/path_depth.ma".
+include "delayed_updating/syntax/path_reverse.ma".
 include "delayed_updating/notation/relations/black_rightarrow_df_4.ma".
 
 (* DELAYED FOCUSED REDUCTION ************************************************)
 
-inductive dfr (p) (q) (t): predicate preterm ≝
-| dfr_beta (b):
-  let r ≝ p●𝗔◗b●𝗟◗q◖𝗱(↑❘q❘) in
-  r ϵ t → ⊓(⊗b) → dfr p q t (t[⋔r←t⋔(p◖𝗦)])
+definition dfr (p) (q): relation2 prototerm prototerm ≝
+           λt1,t2. ∃n:pnat.
+           let r ≝ p●𝗔◗𝗟◗q in
+           ∧∧ (𝗟◗q)ᴿ = ↳[n](rᴿ) & r◖𝗱n ϵ t1 &
+              t1[⋔r←𝛕n.(t1⋔(p◖𝗦))] ⇔ t2
 .
 
 interpretation
-  "focused balanced reduction with delayed updating (preterm)"
+  "focused reduction with delayed updating (prototerm)"
   'BlackRightArrowDF t1 p q t2 = (dfr p q t1 t2).