matita/matita/contribs/lambdadelta/basic_2/relocation/lex.ma

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   3 (*      ||M||                                                             *)
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  14
  15 include "ground_2/relocation/rtmap_uni.ma".
  16 include "basic_2/notation/relations/relation_3.ma".
  17 include "basic_2/syntax/cext2.ma".
  18 include "basic_2/relocation/lexs.ma".
  19
  20 (* GENERIC EXTENSION OF A CONTEXT-SENSITIVE REALTION ON TERMS ***************)
  21
  22 (* Basic_2A1: includes: lpx_sn_atom lpx_sn_pair *)
  23 definition lex: (lenv → relation term) → relation lenv ≝
  24                 λR,L1,L2. ∃∃f. 𝐈⦃f⦄ & L1 ⪤*[cfull, cext2 R, f] L2.
  25
  26 interpretation "generic extension (local environment)"
  27    'Relation R L1 L2 = (lex R L1 L2).
  28
  29 (* Basic properties *********************************************************)
  30
  31 (* Basic_2A1: was: lpx_sn_refl *)
  32 lemma lex_refl: ∀R. c_reflexive … R → reflexive … (lex R).
  33 /4 width=3 by lexs_refl, ext2_refl, ex2_intro/ qed.