Nuprl Lemma : cbv_sqle_2
∀[a,b,X,Y:Base].
  eval x = a in
  X[x] ≤ eval x = b in
         Y[x] 
  supposing ((a)↓ 
⇒ (X[a] ≤ eval x = b in Y[x]))
  ∧ (∀u,v:Base.  ((a ~ exception(u; v)) 
⇒ (eval x = b in Y[x] ~ exception(u; v))))
Proof
Definitions occuring in Statement : 
has-value: (a)↓
, 
callbyvalue: callbyvalue, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
, 
base: Base
, 
sqle: s ≤ t
, 
sqequal: s ~ t
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
has-value: (a)↓
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
guard: {T}
, 
all: ∀x:A. B[x]
Lemmas referenced : 
base_wf, 
all_wf, 
sqle_wf_base, 
and_wf, 
is-exception_wf, 
has-value_wf_base
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
divergentSqle, 
callbyvalueCallbyvalue, 
sqequalHypSubstitution, 
hypothesis, 
sqequalRule, 
callbyvalueReduce, 
productElimination, 
thin, 
independent_functionElimination, 
callbyvalueExceptionCases, 
axiomSqleEquality, 
exceptionSqequal, 
sqleReflexivity, 
lemma_by_obid, 
isectElimination, 
baseApply, 
closedConclusion, 
baseClosed, 
hypothesisEquality, 
functionEquality, 
lambdaEquality, 
sqequalIntensionalEquality, 
isect_memberEquality, 
because_Cache, 
equalityTransitivity, 
equalitySymmetry, 
dependent_functionElimination
Latex:
\mforall{}[a,b,X,Y:Base].
    eval  x  =  a  in
    X[x]  \mleq{}  eval  x  =  b  in
                  Y[x] 
    supposing  ((a)\mdownarrow{}  {}\mRightarrow{}  (X[a]  \mleq{}  eval  x  =  b  in  Y[x]))
    \mwedge{}  (\mforall{}u,v:Base.    ((a  \msim{}  exception(u;  v))  {}\mRightarrow{}  (eval  x  =  b  in  Y[x]  \msim{}  exception(u;  v))))
Date html generated:
2016_05_13-PM-03_45_48
Last ObjectModification:
2016_01_14-PM-07_06_50
Theory : computation
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