matita/matita/contribs/lambdadelta/basic_2A/etc/cpr/ltprs_alt.etc

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  14
  15 notation "hvbox( T1 ➡ ➡ * break term 46 T2 )"
  16    non associative with precedence 45
  17    for @{ 'PRedStarAlt $T1 $T2 }.
  18
  19 include "basic_2/computation/ltprs.ma".
  20
  21 (* CONTEXT-FREE PARALLEL COMPUTATION ON LOCAL ENVIRONMENTS ******************)
  22
  23 (* alternative definition of ltprs *)
  24 definition ltprsa: relation lenv ≝ lpx tprs.
  25
  26 interpretation
  27   "context-free parallel computation (environment) alternative"
  28   'PRedStarAlt L1 L2 = (ltprsa L1 L2).
  29
  30 (* Basic properties *********************************************************)
  31
  32 lemma ltprs_ltprsa: ∀L1,L2. L1 ➡* L2 → L1 ➡➡* L2.
  33 /2 width=1/ qed.
  34
  35 (* Basic inversion lemmas ***************************************************)
  36
  37 lemma ltprsa_ltprs: ∀L1,L2. L1 ➡➡* L2 → L1 ➡* L2.
  38 /2 width=1/ qed-.