Nuprl Lemma : assert-is_int
∀[T:Type]. ∀[x:T]. uiff(↑is_int(x);x ∈ ℤ) supposing value-type(T) ∧ (T ⊆r Base)
Proof
Definitions occuring in Statement : 
is_int: is_int(x), 
value-type: value-type(T), 
assert: ↑b, 
uiff: uiff(P;Q), 
uimplies: b supposing a, 
subtype_rel: A ⊆r B, 
uall: ∀[x:A]. B[x], 
and: P ∧ Q, 
member: t ∈ T, 
int: ℤ, 
base: Base, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
and: P ∧ Q, 
uiff: uiff(P;Q), 
is_int: is_int(x), 
has-value: (a)↓, 
assert: ↑b, 
ifthenelse: if b then t else f fi , 
btrue: tt, 
top: Top, 
bfalse: ff, 
false: False, 
cand: A c∧ B, 
true: True, 
implies: P ⇒ Q, 
subtype_rel: A ⊆r B, 
sq_type: SQType(T), 
all: ∀x:A. B[x], 
guard: {T}
Lemmas referenced : 
value-type-has-value, 
has-value_wf_base, 
is-exception_wf, 
istype-top, 
istype-void, 
istype-assert, 
is_int_wf, 
int-value-type, 
assert_witness, 
istype-int, 
value-type_wf, 
subtype_rel_wf, 
base_wf, 
istype-universe, 
subtype_base_sq, 
int_subtype_base
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
introduction, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
independent_pairFormation, 
sqequalRule, 
callbyvalueReduce, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
independent_isectElimination, 
hypothesis, 
isintCases, 
divergentSqle, 
baseClosed, 
because_Cache, 
isintReduceTrue, 
equalityTransitivity, 
equalitySymmetry, 
axiomSqEquality, 
Error :inhabitedIsType, 
Error :isect_memberEquality_alt, 
Error :isectIsTypeImplies, 
voidElimination, 
axiomEquality, 
intEquality, 
natural_numberEquality, 
independent_functionElimination, 
Error :equalityIstype, 
applyEquality, 
sqequalBase, 
independent_pairEquality, 
Error :universeIsType, 
Error :productIsType, 
instantiate, 
universeEquality, 
cumulativity, 
dependent_functionElimination
Latex:
\mforall{}[T:Type].  \mforall{}[x:T].  uiff(\muparrow{}is\_int(x);x  \mmember{}  \mBbbZ{})  supposing  value-type(T)  \mwedge{}  (T  \msubseteq{}r  Base)
 Date html generated: 
2019_06_20-AM-11_33_09
 Last ObjectModification: 
2019_02_07-PM-00_00_13
Theory : int_1
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