Nuprl Lemma : bag-union-as-combine

∀[A:Type]. ∀[x:bag(bag(A))].  (bag-union(x) = ⋃b∈x.b ∈ bag(A))


Proof




Definitions occuring in Statement :  bag-combine: ⋃x∈bs.f[x],  bag-union: bag-union(bbs),  bag: bag(T),  uall: ∀[x:A]. B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  bag-combine: ⋃x∈bs.f[x],  squash: ↓T,  prop: ℙ,  uimplies: b supposing a,  all: ∀x:A. B[x],  true: True,  subtype_rel: A ⊆r B,  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q
Lemmas referenced :  equal_wf,  squash_wf,  true_wf,  bag_wf,  bag-union_wf,  bag-map-trivial,  subtype_rel_self,  iff_weakening_equal
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalRule,  applyEquality,  thin,  lambdaEquality,  sqequalHypSubstitution,  imageElimination,  extract_by_obid,  isectElimination,  hypothesisEquality,  equalityTransitivity,  hypothesis,  equalitySymmetry,  universeEquality,  because_Cache,  independent_isectElimination,  lambdaFormation,  natural_numberEquality,  imageMemberEquality,  baseClosed,  instantiate,  productElimination,  independent_functionElimination,  isect_memberEquality,  axiomEquality

Latex:
\mforall{}[A:Type].  \mforall{}[x:bag(bag(A))].    (bag-union(x)  =  \mcup{}b\mmember{}x.b)



Date html generated: 2018_05_21-PM-06_24_14
Last ObjectModification: 2018_05_19-PM-05_15_11

Theory : bags


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