Nuprl Lemma : hdf-until-ap-fst

∀[A,B,C:Type]. ∀[X:hdataflow(A;B)]. ∀[Y:hdataflow(A;C)]. ∀[a:A].
  ((fst(hdf-until(X;Y)(a)))
  = if bag-null(snd(Y(a))) then hdf-until(fst(X(a));fst(Y(a))) else hdf-halt() fi 
  ∈ hdataflow(A;B))


Proof




Definitions occuring in Statement :  hdf-until: hdf-until(X;Y),  hdf-halt: hdf-halt(),  hdf-ap: X(a),  hdataflow: hdataflow(A;B),  ifthenelse: if b then t else f fi ,  uall: ∀[x:A]. B[x],  pi1: fst(t),  pi2: snd(t),  universe: Type,  equal: s = t ∈ T,  bag-null: bag-null(bs)
Lemmas :  hdataflow_wf,  bool_wf,  eqtt_to_assert,  assert-bag-null,  hdf-until_wf,  hdf-ap_wf,  bag_wf,  eqff_to_assert,  equal_wf,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  equal-wf-T-base,  hdf-halt_wf,  pi1_wf_top,  squash_wf,  true_wf,  top_wf,  hdf-until-ap,  subtype_rel_product,  subtype_top,  iff_weakening_equal
\mforall{}[A,B,C:Type].  \mforall{}[X:hdataflow(A;B)].  \mforall{}[Y:hdataflow(A;C)].  \mforall{}[a:A].
    ((fst(hdf-until(X;Y)(a)))
    =  if  bag-null(snd(Y(a)))  then  hdf-until(fst(X(a));fst(Y(a)))  else  hdf-halt()  fi  )



Date html generated: 2015_07_17-AM-08_06_09
Last ObjectModification: 2015_02_03-PM-09_46_31

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