X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fdelayed_updating%2Freduction%2Fdfr.ma;h=a610cd323ed07e5f49c0ec63a2c81ca246facb7d;hb=e4328f6887dc0235d49d965a5ba44787b1754b80;hp=135a48b1d149f73674405dfdcf4ddf302314d703;hpb=23e56dd2f1ff99613b69e1ed2a9f26e752304290;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 135a48b1d..a610cd323 100644
--- a/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
+++ b/matita/matita/contribs/lambdadelta/delayed_updating/reduction/dfr.ma
@@ -17,17 +17,19 @@ 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/notation/relations/black_rightarrow_df_4.ma".
+include "delayed_updating/notation/relations/black_rightarrow_df_3.ma".
+include "ground/xoa/ex_4_3.ma".
 
 (* DELAYED FOCUSED REDUCTION ************************************************)
 
-definition dfr (p) (q): relation2 prototerm prototerm ≝
-           λt1,t2. ∃k:pnat.
-           let r ≝ p●𝗔◗𝗟◗q in
-           ∧∧ 𝗟◗q = ↳[k](𝗟◗q) & r◖𝗱k ϵ t1 &
-              t1[⋔r←𝛕k.(t1⋔(p◖𝗦))] ⇔ t2
+(**) (* explicit ninj because we cannot declare the expectd type of k *)
+definition dfr (r): relation2 prototerm prototerm ≝
+           λt1,t2.
+           ∃∃p,q,k. p●𝗔◗𝗟◗q = r &
+           (𝗟◗q) = ↳[ninj k](𝗟◗q) & r◖𝗱k ϵ t1 &
+           t1[⋔r←𝛕k.(t1⋔(p◖𝗦))] ⇔ t2
 .
 
 interpretation
   "focused reduction with delayed updating (prototerm)"
-  'BlackRightArrowDF t1 p q t2 = (dfr p q t1 t2).
+  'BlackRightArrowDF t1 r t2 = (dfr r t1 t2).