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

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  14
  15 include "Basic_2/substitution/lift_vector.ma".
  16
  17 (* GENERIC RELOCATION *******************************************************)
  18
  19 inductive lifts: list2 nat nat → relation term ≝
  20 | lifts_nil : ∀T. lifts ⟠ T T
  21 | lifts_cons: ∀T1,T,T2,des,d,e.
  22               ⇑[d,e] T1 ≡ T → lifts des T T2 → lifts ({d, e} :: des) T1 T2
  23 .
  24
  25 interpretation "generic relocation" 'RLift des T1 T2 = (lifts des T1 T2).