Nuprl Lemma : strictness-decide

∀[F,G:Top].  (case ⊥ of inl(x) => F[x] | inr(x) => G[x] ~ ⊥)


Proof




Definitions occuring in Statement :  bottom: ⊥,  uall: ∀[x:A]. B[x],  top: Top,  so_apply: x[s],  decide: case b of inl(x) => s[x] | inr(y) => t[y],  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,  not: ¬A,  false: False,  bfalse: ff,  top: Top
Lemmas referenced :  injection-eta,  isl_wf,  top_wf,  bool_cases,  subtype_base_sq,  bool_wf,  bool_subtype_base,  eqtt_to_assert,  bottom_diverge,  value-type-has-value,  union-value-type,  eqff_to_assert,  assert_of_bnot,  exception-not-bottom,  has-value_wf_base,  is-exception_wf,  bottom-sqle
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalSqle,  sqleRule,  thin,  divergentSqle,  callbyvalueDecide,  sqequalHypSubstitution,  hypothesis,  baseClosed,  extract_by_obid,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  isectElimination,  because_Cache,  unionElimination,  instantiate,  cumulativity,  independent_isectElimination,  independent_functionElimination,  productElimination,  sqequalRule,  voidElimination,  decideExceptionCases,  axiomSqleEquality,  unionEquality,  baseApply,  closedConclusion,  hypothesisEquality,  sqleReflexivity,  isect_memberEquality,  voidEquality,  sqequalAxiom

Latex:
\mforall{}[F,G:Top].    (case  \mbot{}  of  inl(x)  =>  F[x]  |  inr(x)  =>  G[x]  \msim{}  \mbot{})



Date html generated: 2018_05_21-PM-00_02_19
Last ObjectModification: 2018_05_19-AM-07_12_51

Theory : computation


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