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
Home
Index