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 then else fi  uall: [x:A]. B[x] pi1: fst(t) pi2: snd(t) universe: Type equal: 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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