Nuprl Lemma : decide-append

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


Proof




Definitions occuring in Statement :  append: as @ bs,  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,  so_apply: x[s],  append: as @ bs,  cons: [a / b],  list_ind: list_ind,  so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]),  so_apply: x[s1;s2;s3;s4],  so_lambda: λ2x.t[x],  top: Top,  uimplies: b supposing a,  strict4: strict4(F),  and: P ∧ Q,  all: ∀x:A. B[x],  implies: P ⇒ Q,  has-value: (a)↓,  prop: ℙ,  guard: {T},  or: P ∨ Q,  squash: ↓T
Lemmas referenced :  top_wf,  is-exception_wf,  base_wf,  has-value_wf_base,  lifting-strict-decide
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalRule,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  baseClosed,  isect_memberEquality,  voidElimination,  voidEquality,  independent_isectElimination,  independent_pairFormation,  lambdaFormation,  callbyvalueCallbyvalue,  hypothesis,  callbyvalueReduce,  baseApply,  closedConclusion,  hypothesisEquality,  callbyvalueExceptionCases,  inrFormation,  imageMemberEquality,  imageElimination,  exceptionSqequal,  inlFormation,  sqequalAxiom,  because_Cache

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



Date html generated: 2016_05_15-PM-02_07_49
Last ObjectModification: 2016_01_15-PM-10_22_06

Theory : untyped!computation


Home Index