Nuprl Lemma : fpf-cap-subtype_functionality_wrt_sub2
∀[A1,A2,A3:Type]. ∀[d,d':EqDecider(A3)]. ∀[d2:EqDecider(A2)]. ∀[f:a:A1 fp-> Type]. ∀[g:a:A2 fp-> Type]. ∀[x:A3].
  ({g(x)?Top ⊆r f(x)?Top supposing f ⊆ g}) supposing (strong-subtype(A2;A3) and strong-subtype(A1;A2))
Proof
Definitions occuring in Statement : 
fpf-sub: f ⊆ g
, 
fpf-cap: f(x)?z
, 
fpf: a:A fp-> B[a]
, 
deq: EqDecider(T)
, 
strong-subtype: strong-subtype(A;B)
, 
uimplies: b supposing a
, 
subtype_rel: A ⊆r B
, 
uall: ∀[x:A]. B[x]
, 
top: Top
, 
guard: {T}
, 
universe: Type
Definitions unfolded in proof : 
guard: {T}
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
subtype_rel: A ⊆r B
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
top: Top
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
fpf-sub: f ⊆ g
, 
implies: P 
⇒ Q
, 
strong-subtype: strong-subtype(A;B)
, 
cand: A c∧ B
, 
fpf-ap: f(x)
, 
pi2: snd(t)
, 
fpf-cap: f(x)?z
, 
bool: 𝔹
, 
unit: Unit
, 
it: ⋅
, 
btrue: tt
, 
uiff: uiff(P;Q)
, 
and: P ∧ Q
, 
ifthenelse: if b then t else f fi 
, 
bfalse: ff
, 
not: ¬A
, 
false: False
Lemmas referenced : 
strong-subtype_transitivity, 
fpf-sub_wf, 
subtype-fpf3, 
subtype_rel_self, 
strong-subtype_wf, 
fpf_wf, 
deq_wf, 
decidable__assert, 
fpf-dom_wf, 
top_wf, 
fpf-cap_wf, 
subtype_rel_wf, 
fpf-cap_functionality_wrt_sub, 
assert_wf, 
fpf-dom-type2, 
subtype-fpf2, 
fpf-dom_functionality2, 
strong-subtype-deq-subtype, 
bool_wf, 
equal-wf-T-base, 
bnot_wf, 
not_wf, 
eqtt_to_assert, 
uiff_transitivity, 
eqff_to_assert, 
assert_of_bnot, 
equal_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
because_Cache, 
independent_isectElimination, 
hypothesis, 
axiomEquality, 
instantiate, 
cumulativity, 
lambdaEquality, 
universeEquality, 
applyEquality, 
lambdaFormation, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
dependent_functionElimination, 
voidElimination, 
voidEquality, 
unionElimination, 
hyp_replacement, 
applyLambdaEquality, 
productElimination, 
independent_functionElimination, 
independent_pairFormation, 
baseClosed, 
equalityElimination
Latex:
\mforall{}[A1,A2,A3:Type].  \mforall{}[d,d':EqDecider(A3)].  \mforall{}[d2:EqDecider(A2)].  \mforall{}[f:a:A1  fp->  Type].
\mforall{}[g:a:A2  fp->  Type].  \mforall{}[x:A3].
    (\{g(x)?Top  \msubseteq{}r  f(x)?Top  supposing  f  \msubseteq{}  g\})  supposing 
          (strong-subtype(A2;A3)  and 
          strong-subtype(A1;A2))
Date html generated:
2018_05_21-PM-09_19_47
Last ObjectModification:
2018_02_09-AM-10_17_43
Theory : finite!partial!functions
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