Nuprl Lemma : sumdeq_wf
∀[A,B:Type]. ∀[a:EqDecider(A)]. ∀[b:EqDecider(B)].  (sumdeq(a;b) ∈ (A + B) ⟶ (A + B) ⟶ 𝔹)
Proof
Definitions occuring in Statement : 
sumdeq: sumdeq(a;b)
, 
deq: EqDecider(T)
, 
bool: 𝔹
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
function: x:A ⟶ B[x]
, 
union: left + right
, 
universe: Type
Definitions unfolded in proof : 
sumdeq: sumdeq(a;b)
, 
deq: EqDecider(T)
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
and: P ∧ Q
Lemmas referenced : 
bfalse_wf, 
equal_wf, 
set_wf, 
bool_wf, 
all_wf, 
iff_wf, 
assert_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
introduction, 
cut, 
lambdaEquality, 
hypothesisEquality, 
equalityTransitivity, 
hypothesis, 
equalitySymmetry, 
thin, 
unionEquality, 
lambdaFormation, 
unionElimination, 
applyEquality, 
setElimination, 
rename, 
sqequalHypSubstitution, 
extract_by_obid, 
isectElimination, 
dependent_functionElimination, 
independent_functionElimination, 
axiomEquality, 
functionEquality, 
isect_memberEquality, 
because_Cache, 
universeEquality
Latex:
\mforall{}[A,B:Type].  \mforall{}[a:EqDecider(A)].  \mforall{}[b:EqDecider(B)].    (sumdeq(a;b)  \mmember{}  (A  +  B)  {}\mrightarrow{}  (A  +  B)  {}\mrightarrow{}  \mBbbB{})
Date html generated:
2019_06_20-PM-00_32_02
Last ObjectModification:
2018_08_21-PM-01_53_07
Theory : equality!deciders
Home
Index