Nuprl Lemma : isr-first-success
∀[T:Type]. ∀[A:T ⟶ Type]. ∀[f:x:T ⟶ (A[x]?)]. ∀[L:T List].  (↑isr(first-success(f;L)) 
⇐⇒ (∀a∈L.↑isr(f a)))
Proof
Definitions occuring in Statement : 
l_all: (∀x∈L.P[x])
, 
first-success: first-success(f;L)
, 
list: T List
, 
assert: ↑b
, 
isr: isr(x)
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
iff: P 
⇐⇒ Q
, 
unit: Unit
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
union: left + right
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
so_lambda: λ2x.t[x]
, 
prop: ℙ
, 
so_apply: x[s]
, 
uimplies: b supposing a
, 
all: ∀x:A. B[x]
, 
top: Top
, 
int_seg: {i..j-}
, 
sq_stable: SqStable(P)
, 
lelt: i ≤ j < k
, 
squash: ↓T
, 
first-success: first-success(f;L)
, 
so_lambda: so_lambda(x,y,z.t[x; y; z])
, 
so_apply: x[s1;s2;s3]
, 
isr: isr(x)
, 
assert: ↑b
, 
ifthenelse: if b then t else f fi 
, 
bfalse: ff
, 
false: False
, 
btrue: tt
, 
unit: Unit
, 
cand: A c∧ B
, 
true: True
, 
rev_implies: P 
⇐ Q
, 
list_ind: list_ind, 
nil: []
, 
it: ⋅
, 
subtype_rel: A ⊆r B
, 
l_all: (∀x∈L.P[x])
Lemmas referenced : 
list_induction, 
assert_wf, 
isr_wf, 
select_wf, 
l_all_wf, 
l_member_wf, 
list_wf, 
l_all_nil, 
int_seg_wf, 
length_wf, 
nil_wf, 
sq_stable__le, 
unit_wf2, 
first-success_wf, 
list_ind_cons_lemma, 
false_wf, 
true_wf, 
equal_wf, 
l_all_cons, 
l_all_wf_nil, 
cons_wf, 
assert_witness
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
independent_pairFormation, 
lambdaFormation, 
thin, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
sqequalRule, 
lambdaEquality, 
functionEquality, 
productEquality, 
because_Cache, 
applyEquality, 
independent_isectElimination, 
hypothesis, 
cumulativity, 
setElimination, 
rename, 
functionExtensionality, 
setEquality, 
independent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
natural_numberEquality, 
productElimination, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
dependent_functionElimination, 
unionEquality, 
unionElimination, 
equalityElimination, 
equalityTransitivity, 
equalitySymmetry, 
addLevel, 
impliesFunctionality, 
independent_pairEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}[A:T  {}\mrightarrow{}  Type].  \mforall{}[f:x:T  {}\mrightarrow{}  (A[x]?)].  \mforall{}[L:T  List].
    (\muparrow{}isr(first-success(f;L))  \mLeftarrow{}{}\mRightarrow{}  (\mforall{}a\mmember{}L.\muparrow{}isr(f  a)))
Date html generated:
2017_04_14-AM-08_41_00
Last ObjectModification:
2017_02_27-PM-03_31_43
Theory : list_0
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