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update in delayed_updating
[helm.git] / matita / matita / contribs / lambdadelta / delayed_updating / reduction / dfr.ma
index 3dca53142fb3a3e6fabc1d31a0fd34f1795831d1..ed077ae2cc772df22b7227dab1750ace5c243afd 100644 (file)
 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/substitution/fsubst.ma".
 include "delayed_updating/notation/relations/black_rightarrow_df_4.ma".
 
 (* DELAYED FOCUSED REDUCTION ************************************************)
 
-inductive dfr (p) (q) (t): predicate preterm ≝
+inductive dfr (p) (q) (t): predicate prototerm ≝
 | 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)])
+  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)])
 .
 
 interpretation
-  "focused balanced reduction with delayed updating (preterm)"
+  "focused balanced reduction with delayed updating (prototerm)"
   'BlackRightArrowDF t1 p q t2 = (dfr p q t1 t2).