matita/matita/contribs/lambda-delta/Basic-2/grammar/term.ma

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   3 (*      ||M||                                                             *)
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   5 (*      ||T||                                                             *)
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  14
  15 include "Basic-2/grammar/item.ma".
  16
  17 (* TERMS ********************************************************************)
  18
  19 (* terms *)
  20 inductive term: Type[0] ≝
  21 | TSort: nat → term                 (* sort: starting at 0 *)
  22 | TLRef: nat → term                 (* reference by index: starting at 0 *)
  23 | TPair: item2 → term → term → term (* binary item construction *)
  24 .
  25
  26 interpretation "sort (term)" 'Star k = (TSort k).
  27
  28 interpretation "local reference (term)" 'LRef i = (TLRef i).
  29
  30 interpretation "term construction (binary)" 'SItem I T1 T2 = (TPair I T1 T2).
  31
  32 interpretation "term binding construction (binary)" 'SBind I T1 T2 = (TPair (Bind I) T1 T2).
  33
  34 interpretation "term flat construction (binary)" 'SFlat I T1 T2 = (TPair (Flat I) T1 T2).