Nuprl Lemma : filter-as-mapfilter

∀[L,P:Top].  (filter(P;L) ~ mapfilter(λx.x;P;L))


Proof




Definitions occuring in Statement :  mapfilter: mapfilter(f;P;L),  filter: filter(P;l),  uall: ∀[x:A]. B[x],  top: Top,  lambda: λx.A[x],  sqequal: s ~ t
Definitions unfolded in proof :  mapfilter: mapfilter(f;P;L),  uall: ∀[x:A]. B[x],  member: t ∈ T,  filter: filter(P;l),  reduce: reduce(f;k;as),  so_lambda: λ2x.t[x],  so_apply: x[s],  uimplies: b supposing a,  strict1: strict1(F),  and: P ∧ Q,  all: ∀x:A. B[x],  implies: P ⇒ Q,  prop: ℙ,  guard: {T},  or: P ∨ Q,  squash: ↓T,  map: map(f;as),  list_ind: list_ind,  has-value: (a)↓,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3],  top: Top
Lemmas referenced :  top_wf,  map_nil_lemma,  sqle_wf_base,  map_cons_lemma,  map-ifthenelse,  is-exception_wf,  base_wf,  has-value_wf_base,  sqequal-list_ind
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  introduction,  cut,  thin,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  baseClosed,  independent_isectElimination,  independent_pairFormation,  lambdaFormation,  hypothesis,  baseApply,  closedConclusion,  hypothesisEquality,  inrFormation,  imageMemberEquality,  callbyvalueCallbyvalue,  callbyvalueReduce,  callbyvalueExceptionCases,  inlFormation,  imageElimination,  exceptionSqequal,  isect_memberEquality,  voidElimination,  voidEquality,  dependent_functionElimination,  divergentSqle,  sqleRule,  sqleReflexivity,  because_Cache,  sqequalAxiom

Latex:
\mforall{}[L,P:Top].    (filter(P;L)  \msim{}  mapfilter(\mlambda{}x.x;P;L))



Date html generated: 2016_05_14-PM-01_29_21
Last ObjectModification: 2016_01_15-AM-08_28_17

Theory : list_1


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