Nuprl Lemma : normalize-decide-left
∀[a,F,G:Top].  (case a of inl(x) => F[x] a | inr(x) => G[x] ~ case a of inl(x) => F[x] (inl x) | inr(x) => G[x])
Proof
Definitions occuring in Statement : 
uall: ∀[x:A]. B[x], 
top: Top, 
so_apply: x[s], 
apply: f a, 
decide: case b of inl(x) => s[x] | inr(y) => t[y], 
inl: inl x, 
sqequal: s ~ t
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
has-value: (a)↓, 
all: ∀x:A. B[x], 
or: P ∨ Q, 
uimplies: b supposing a, 
sq_type: SQType(T), 
implies: P ⇒ Q, 
guard: {T}, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
ifthenelse: if b then t else f fi , 
btrue: tt, 
bfalse: ff
Lemmas referenced : 
assert_of_bnot, 
eqff_to_assert, 
is-exception_wf, 
has-value_wf_base, 
eqtt_to_assert, 
bool_subtype_base, 
bool_wf, 
subtype_base_sq, 
bool_cases, 
top_wf, 
isl_wf, 
injection-eta
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
sqequalSqle, 
sqleRule, 
thin, 
divergentSqle, 
callbyvalueDecide, 
sqequalHypSubstitution, 
hypothesis, 
lemma_by_obid, 
dependent_functionElimination, 
equalityTransitivity, 
equalitySymmetry, 
isectElimination, 
because_Cache, 
unionElimination, 
instantiate, 
cumulativity, 
independent_isectElimination, 
independent_functionElimination, 
productElimination, 
sqequalRule, 
sqleReflexivity, 
baseApply, 
closedConclusion, 
baseClosed, 
hypothesisEquality, 
decideExceptionCases, 
axiomSqleEquality, 
exceptionSqequal, 
sqequalAxiom, 
isect_memberEquality
Latex:
\mforall{}[a,F,G:Top].
    (case  a  of  inl(x)  =>  F[x]  a  |  inr(x)  =>  G[x]  \msim{}  case  a  of  inl(x)  =>  F[x]  (inl  x)  |  inr(x)  =>  G[x])
Date html generated:
2016_05_13-PM-03_43_21
Last ObjectModification:
2016_01_14-PM-07_08_30
Theory : computation
Home
Index