]> matita.cs.unibo.it Git - helm.git/blobdiff - matita/matita/contribs/lambdadelta/delayed_updating/reduction/ifr.ma
update in delayed_updating
[helm.git] / matita / matita / contribs / lambdadelta / delayed_updating / reduction / ifr.ma
index 765387b1c4243749c9687e883f52996660f2d879..b36038141c87ce356fb4296899ef3daac03269cf 100644 (file)
@@ -16,18 +16,20 @@ include "delayed_updating/substitution/fsubst.ma".
 include "delayed_updating/substitution/lift_prototerm.ma".
 include "delayed_updating/syntax/prototerm_eq.ma".
 include "delayed_updating/syntax/path_head.ma".
-include "delayed_updating/syntax/path_reverse.ma".
-include "delayed_updating/notation/relations/black_rightarrow_if_4.ma".
+include "delayed_updating/notation/relations/black_rightarrow_if_3.ma".
+include "ground/relocation/tr_uni.ma".
+include "ground/xoa/ex_4_3.ma".
 
 (* IMMEDIATE FOCUSED REDUCTION ************************************************)
 
-definition ifr (p) (q): relation2 prototerm prototerm ≝
-           λt1,t2. ∃n:pnat.
-           let r ≝ p●𝗔◗𝗟◗q in
-           ∧∧ (𝗟◗q)ᴿ = ↳[n](𝗟◗q)ᴿ & r◖𝗱n ϵ t1 &
-              t1[⋔r←↑[𝐮❨n❩](t1⋔(p◖𝗦))] ⇔ t2
+(**) (* explicit ninj because we cannot declare the expectd type of k *)
+definition ifr (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←↑[𝐮❨ninj k❩](t1⋔(p◖𝗦))] ⇔ t2
 .
 
 interpretation
   "focused reduction with immediate updating (prototerm)"
-  'BlackRightArrowIF t1 p q t2 = (ifr p q t1 t2).
+  'BlackRightArrowIF t1 r t2 = (ifr r t1 t2).