matita/matita/contribs/lambda_delta/Basic_2/unfold/ldrops.ma

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  14
  15 include "Basic_2/substitution/ldrop.ma".
  16 include "Basic_2/unfold/lifts.ma".
  17
  18 (* GENERIC LOCAL ENVIRONMENT SLICING ****************************************)
  19
  20 inductive ldrops: list2 nat nat → relation lenv ≝
  21 | ldrops_nil : ∀L. ldrops ⟠ L L
  22 | ldrops_cons: ∀L1,L,L2,des,d,e.
  23                ⇓[d,e] L1 ≡ L → ldrops des L L2 → ldrops ({d, e} :: des) L1 L2
  24 .
  25
  26 interpretation "generic local environment slicing"
  27    'RDrop des T1 T2 = (ldrops des T1 T2).