matita/matita/contribs/lambda_delta/Basic_2/grammar/term.ma

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   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
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  14
  15 include "Basic_2/grammar/item.ma".
  16
  17 (* TERMS ********************************************************************)
  18
  19 (* terms *)
  20 inductive term: Type[0] ≝
  21   | TAtom: item0 → term               (* atomic item construction *)
  22   | TPair: item2 → term → term → term (* binary item construction *)
  23 .
  24
  25 interpretation "sort (term)" 'Star k = (TAtom (Sort k)).
  26
  27 interpretation "local reference (term)" 'LRef i = (TAtom (LRef i)).
  28
  29 interpretation "term construction (atomic)" 'SItem I = (TAtom I).
  30
  31 interpretation "term construction (binary)" 'SItem I T1 T2 = (TPair I T1 T2).
  32
  33 interpretation "term binding construction (binary)" 'SBind I T1 T2 = (TPair (Bind I) T1 T2).
  34
  35 interpretation "term flat construction (binary)" 'SFlat I T1 T2 = (TPair (Flat I) T1 T2).