matita/contribs/LOGIC/datatypes_defs/Proof.ma

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   3 (*      ||M||                                                             *)
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  11 (*        v         GNU General Public License Version 2                  *)
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  14
  15
  16
  17 (* PROOFS
  18    - Naming policy:
  19      - proofs: p q r s
  20 *)
  21
  22 include "preamble0.ma".
  23
  24 inductive Proof: Type \def
  25    | lref: Nat \to Proof                       (* projection         *)
  26    | prin: Nat \to Proof                       (* pos rel inhabitant *)
  27    | impw: Proof \to Proof                     (* weakening          *)
  28    | impr: Proof \to Proof                     (* right introduction *)
  29    | impi: Proof \to Proof \to Proof \to Proof (* left introduction  *)
  30    | scut: Proof \to Proof \to Proof           (* symmetric cut      *)
  31 .