matita/contribs/LOGIC/PNF/defs.ma

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  14
  15 set "baseuri" "cic:/matita/LOGIC/PNF/defs".
  16
  17 (* NORMAL FORM PREDICATE FOR PROOFS IN CONTEXT
  18    For cut elimination
  19 *)
  20
  21 include "PEq/defs.ma".
  22 include "PRed/defs.ma".
  23
  24 inductive PNF (P:Context) (p:Proof): Prop \def
  25    | pnf: (\forall q,Q,S. [P, p, S] => [Q, q, S] \to [P, p] = [Q, q]) \to
  26           PNF P p
  27 .