Nuprl Lemma : bag-remove1-property1

[T:Type]
  ∀eq:EqDecider(T). ∀x:T. ∀L:T List.
    ((∃as,bs:T List. ((L ((as [x]) bs) ∈ (T List)) ∧ (bag-remove1(eq;L;x) (inl (rev(as) bs)) ∈ (T List?))))
    ∨ ((¬(x ∈ L)) ∧ (bag-remove1(eq;L;x) (inr ⋅ ) ∈ (T List?))))


Proof




Definitions occuring in Statement :  bag-remove1: bag-remove1(eq;bs;a) l_member: (x ∈ l) reverse: rev(as) append: as bs cons: [a b] nil: [] list: List deq: EqDecider(T) it: uall: [x:A]. B[x] all: x:A. B[x] exists: x:A. B[x] not: ¬A or: P ∨ Q and: P ∧ Q unit: Unit inr: inr  inl: inl x union: left right universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T all: x:A. B[x] bag-remove1: bag-remove1(eq;bs;a) or: P ∨ Q exists: x:A. B[x] and: P ∧ Q subtype_rel: A ⊆B uimplies: supposing a top: Top prop: cand: c∧ B so_lambda: λ2x.t[x] so_apply: x[s] guard: {T}
Lemmas referenced :  bag_remove1_aux_property nil_wf append-nil reverse_wf subtype_rel_list top_wf equal_wf list_wf append_wf cons_wf length_wf length-append exists_wf not_wf l_member_wf equal-wf-T-base unit_wf2 bag_remove1_aux_wf deq_wf
Rules used in proof :  cut introduction extract_by_obid sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation hypothesis sqequalHypSubstitution isectElimination thin hypothesisEquality lambdaFormation dependent_functionElimination cumulativity unionElimination inlFormation productElimination dependent_pairFormation independent_pairFormation promote_hyp sqequalRule applyEquality independent_isectElimination lambdaEquality isect_memberEquality voidElimination voidEquality because_Cache productEquality applyLambdaEquality unionEquality baseClosed inrFormation universeEquality

Latex:
\mforall{}[T:Type]
    \mforall{}eq:EqDecider(T).  \mforall{}x:T.  \mforall{}L:T  List.
        ((\mexists{}as,bs:T  List.  ((L  =  ((as  @  [x])  @  bs))  \mwedge{}  (bag-remove1(eq;L;x)  =  (inl  (rev(as)  @  bs)))))
        \mvee{}  ((\mneg{}(x  \mmember{}  L))  \mwedge{}  (bag-remove1(eq;L;x)  =  (inr  \mcdot{}  ))))



Date html generated: 2018_05_21-PM-09_48_06
Last ObjectModification: 2017_07_26-PM-06_30_33

Theory : bags_2


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