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: 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: supposing a strict1: strict1(F) and: P ∧ Q all: x:A. B[x] implies:  Q prop: 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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