matita/matita/contribs/lambdadelta/basic_2/static/gcp.ma

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   3 (*      ||M||                                                             *)
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  14
  15 include "basic_2/syntax/genv.ma".
  16 include "basic_2/relocation/drops_vector.ma".
  17
  18 (* GENERIC COMPUTATION PROPERTIES *******************************************)
  19
  20 definition nf ≝ λRR:relation4 genv lenv term term. λRS:relation term.
  21                 λG,L,T. NF … (RR G L) RS T.
  22
  23 definition candidate: Type[0] ≝ relation3 genv lenv term.
  24
  25 definition CP0 ≝ λRR:relation4 genv lenv term term. λRS:relation term.
  26                  ∀G. d_liftable1 (nf RR RS G).
  27
  28 definition CP1 ≝ λRR:relation4 genv lenv term term. λRS:relation term.
  29                  ∀G,L. ∃s. NF … (RR G L) RS (⋆s).
  30
  31 definition CP2 ≝ λRP:candidate. ∀G. d_liftable1 (RP G).
  32
  33 definition CP3 ≝ λRP:candidate.
  34                  ∀G,L,T,s. RP G L (ⓐ⋆s.T) → RP G L T.
  35
  36 (* requirements for generic computation properties *)
  37 (* Basic_1: includes: nf2_lift1 *)
  38 (* Basic_2A1: includes: gcp0_lifts *)
  39 (* Basic_2A1: includes: gcp2_lifts *)
  40 record gcp (RR:relation4 genv lenv term term) (RS:relation term) (RP:candidate) : Prop ≝
  41 { cp0: CP0 RR RS;
  42   cp1: CP1 RR RS;
  43   cp2: CP2 RP;
  44   cp3: CP3 RP
  45 }.
  46
  47 (* Basic properties *********************************************************)
  48
  49 (* Basic_1: was only: sns3_lifts1 *)
  50 (* Basic_2A1: was: gcp2_lifts_all *)
  51 lemma gcp2_all: ∀RR,RS,RP. gcp RR RS RP → ∀G. d_liftable1_all (RP G).
  52 /3 width=7 by cp2, d1_liftable_liftable_all/ qed.