matita/matita/contribs/lambda_delta/basic_2/computation/ltprs_alt.ma

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  14
  15 include "basic_2/computation/ltprs.ma".
  16
  17 (* CONTEXT-FREE PARALLEL COMPUTATION ON LOCAL ENVIRONMENTS ******************)
  18
  19 (* alternative definition of ltprs *)
  20 definition ltprsa: relation lenv ≝ lpx tprs.
  21
  22 interpretation
  23   "context-free parallel computation (environment) alternative"
  24   'PRedStarAlt L1 L2 = (ltprsa L1 L2).
  25
  26 (* Basic properties *********************************************************)
  27
  28 lemma ltprs_ltprsa: ∀L1,L2. L1 ➡* L2 → L1 ➡➡* L2.
  29 /2 width=1/ qed.
  30
  31 (* Basic inversion lemmas ***************************************************)
  32
  33 lemma ltprsa_ltprs: ∀L1,L2. L1 ➡➡* L2 → L1 ➡* L2.
  34 /2 width=1/ qed-.