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

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  14
  15 include "Basic-2/grammar/lenv_weight.ma".
  16
  17 (* WEIGHT OF A CLOSURE ******************************************************)
  18
  19 definition cw: lenv → term → ? ≝ λL,T. #[L] + #[T].
  20
  21 interpretation "weight (closure)" 'Weight L T = (cw L T).
  22
  23 (* Basic properties *********************************************************)
  24
  25 lemma cw_shift: ∀K,I,V,T. #[K. 𝕓{I} V, T] < #[K, 𝕓{I} V. T].
  26 normalize //
  27 qed.
  28
  29 axiom cw_wf_ind: ∀R:lenv→term→Prop.
  30                  (∀L2,T2. (∀L1,T1. #[L1,T1] < #[L2,T2] → R L1 T1) → R L2 T2) →
  31                  ∀L,T. R L T.