Nuprl Lemma : hdf-until-ap

[A,B,C:Type]. ∀[X:hdataflow(A;B)]. ∀[Y:hdataflow(A;C)]. ∀[a:A].
  (hdf-until(X;Y)(a)
  = <if bag-null(snd(Y(a))) then hdf-until(fst(X(a));fst(Y(a))) else hdf-halt() fi snd(X(a))>
  ∈ (hdataflow(A;B) × bag(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) pair: <a, b> product: x:A × B[x] universe: Type equal: t ∈ T bag-null: bag-null(bs) bag: bag(T)
Lemmas :  hdf-halted_wf eqtt_to_assert hdf_ap_halt_lemma assert-bag-null hdataflow-ext bag_wf unit_wf2 hdf_halted_inl_red_lemma false_wf hdf_halted_halt_red_lemma hdataflow_wf hdf-ap-inl hdf-halt_wf empty-bag_wf equal-wf-T-base hdf-ap_wf hdf-run_wf equal-wf-base true_wf eqff_to_assert equal_wf bool_wf bool_cases_sqequal subtype_base_sq bool_subtype_base assert-bnot hdf-ap-run pi2_wf squash_wf iff_weakening_equal bag_null_empty_lemma hdf-until_wf bag-null_wf not_wf
\mforall{}[A,B,C:Type].  \mforall{}[X:hdataflow(A;B)].  \mforall{}[Y:hdataflow(A;C)].  \mforall{}[a:A].
    (hdf-until(X;Y)(a)
    =  <if  bag-null(snd(Y(a)))  then  hdf-until(fst(X(a));fst(Y(a)))  else  hdf-halt()  fi  ,  snd(X(a))>)



Date html generated: 2015_07_17-AM-08_06_08
Last ObjectModification: 2015_02_03-PM-09_47_22

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