Nuprl Lemma : list-ext
∀[A:Type]. A List ≡ Unit ⋃ (A × (A List))
Proof
Definitions occuring in Statement : 
list: T List, 
b-union: A ⋃ B, 
ext-eq: A ≡ B, 
uall: ∀[x:A]. B[x], 
unit: Unit, 
product: x:A × B[x], 
universe: Type
Definitions unfolded in proof : 
list: T List, 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
ext-eq: A ≡ B, 
and: P ∧ Q, 
subtype_rel: A ⊆r B, 
uimplies: b supposing a, 
nat: ℕ, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
prop: ℙ, 
b-union: A ⋃ B, 
tunion: ⋃x:A.B[x], 
bool: 𝔹, 
unit: Unit, 
ifthenelse: if b then t else f fi , 
pi2: snd(t), 
btrue: tt, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
it: ⋅, 
uiff: uiff(P;Q), 
bfalse: ff, 
exists: ∃x:A. B[x], 
or: P ∨ Q, 
sq_type: SQType(T), 
guard: {T}, 
bnot: ¬bb, 
assert: ↑b, 
false: False, 
colength: colength(L), 
has-value: (a)↓
Lemmas referenced : 
colist-ext, 
colist_wf, 
has-value_wf-partial, 
nat_wf, 
set-value-type, 
le_wf, 
int-value-type, 
colength_wf, 
b-union_wf, 
unit_wf2, 
btrue_wf, 
bool_wf, 
eqtt_to_assert, 
eqff_to_assert, 
equal_wf, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_subtype_base, 
assert-bnot, 
bfalse_wf, 
subtype_partial_sqtype_base, 
set_subtype_base, 
int_subtype_base, 
value-type-has-value, 
subtype_rel_b-union-left, 
subtype_rel_transitivity, 
has-value_wf_base, 
is-exception_wf, 
subtype_rel_b-union-right, 
termination
Rules used in proof : 
cut, 
introduction, 
extract_by_obid, 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
independent_pairFormation, 
productElimination, 
promote_hyp, 
lambdaEquality, 
setEquality, 
cumulativity, 
independent_isectElimination, 
intEquality, 
natural_numberEquality, 
because_Cache, 
productEquality, 
universeEquality, 
setElimination, 
rename, 
hypothesis_subsumption, 
applyEquality, 
imageElimination, 
unionElimination, 
equalityElimination, 
imageMemberEquality, 
dependent_pairEquality, 
lambdaFormation, 
equalityTransitivity, 
equalitySymmetry, 
dependent_pairFormation, 
dependent_functionElimination, 
instantiate, 
independent_functionElimination, 
voidElimination, 
baseClosed, 
independent_pairEquality, 
callbyvalueAdd, 
dependent_set_memberEquality, 
divergentSqle, 
sqleReflexivity, 
addEquality
Latex:
\mforall{}[A:Type].  A  List  \mequiv{}  Unit  \mcup{}  (A  \mtimes{}  (A  List))
Date html generated:
2017_04_14-AM-07_54_14
Last ObjectModification:
2017_02_27-PM-03_21_08
Theory : list_0
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