Nuprl Lemma : member-filter

[T:Type]. ∀P:T ⟶ 𝔹. ∀L:T List. ∀x:{x:T| ↑P[x]} .  ((x ∈ filter(λx.P[x];L)) ⇐⇒ (x ∈ L))


Proof




Definitions occuring in Statement :  l_member: (x ∈ l) filter: filter(P;l) list: List assert: b bool: 𝔹 uall: [x:A]. B[x] so_apply: x[s] all: x:A. B[x] iff: ⇐⇒ Q set: {x:A| B[x]}  lambda: λx.A[x] function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] member: t ∈ T so_lambda: λ2x.t[x] prop: so_apply: x[s] implies:  Q iff: ⇐⇒ Q and: P ∧ Q uimplies: supposing a not: ¬A false: False rev_implies:  Q bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) ifthenelse: if then else fi  bfalse: ff exists: x:A. B[x] or: P ∨ Q sq_type: SQType(T) guard: {T} bnot: ¬bb assert: b squash: T true: True
Lemmas referenced :  list_induction assert_wf iff_wf l_member_wf filter_type list_wf filter_nil_lemma null_nil_lemma btrue_wf member-implies-null-eq-bfalse nil_wf istype-assert btrue_neq_bfalse filter_cons_lemma eqtt_to_assert eqff_to_assert bool_cases_sqequal subtype_base_sq bool_wf bool_subtype_base assert-bnot istype-universe equal_functionality_wrt_subtype_rel2 subtype_rel_set_simple cons_member cons_wf assert_elim equal_wf and_wf not_assert_elim or_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt lambdaFormation_alt cut thin introduction extract_by_obid sqequalHypSubstitution isectElimination hypothesisEquality sqequalRule lambdaEquality_alt functionEquality setEquality applyEquality hypothesis universeIsType setElimination rename independent_functionElimination dependent_functionElimination Error :memTop,  independent_pairFormation dependent_set_memberEquality_alt independent_isectElimination equalityTransitivity equalitySymmetry voidElimination because_Cache setIsType inhabitedIsType unionElimination equalityElimination productElimination dependent_pairFormation_alt equalityIstype promote_hyp instantiate cumulativity functionIsType productIsType universeEquality inlFormation_alt inrFormation_alt unionIsType applyLambdaEquality imageMemberEquality baseClosed imageElimination inlFormation natural_numberEquality dependent_set_memberEquality inrFormation lambdaFormation lambdaEquality

Latex:
\mforall{}[T:Type].  \mforall{}P:T  {}\mrightarrow{}  \mBbbB{}.  \mforall{}L:T  List.  \mforall{}x:\{x:T|  \muparrow{}P[x]\}  .    ((x  \mmember{}  filter(\mlambda{}x.P[x];L))  \mLeftarrow{}{}\mRightarrow{}  (x  \mmember{}  L))



Date html generated: 2020_05_19-PM-09_37_46
Last ObjectModification: 2020_01_04-PM-07_57_53

Theory : list_0


Home Index