matita/matita/lib/lambda/terms/supercombinator.ma

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   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
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  14
  15 include "lambda/terms/term.ma".
  16
  17 (* SUPERCOMBINATOR **********************************************************)
  18
  19 inductive is_supercombinator: nat → nat → predicate term ≝
  20 | is_supercombinator_vref:
  21   ∀i,d. i < d → ∀h. is_supercombinator h d (#i)
  22 | is_supercombinator_abst:
  23   ∀A,h. is_supercombinator (S h) (S h) A → ∀d. is_supercombinator h d (𝛌.A)
  24 | is_supercombinator_appl:
  25   ∀B,A,d. is_supercombinator 0 d B → is_supercombinator 0 d A →
  26   ∀h. is_supercombinator h d (@B.A)
  27 .