Nuprl Lemma : bag-remove1-equal

∀[T:Type]. ∀[eq:EqDecider(T)]. ∀[as,bs:bag(T)]. ∀[a,b:T].
  uiff(bag-remove1(eq;as;a) = bag-remove1(eq;bs;b) ∈ (bag(T)?);(({a} + bs) = ({b} + as) ∈ bag(T))
  ↓∨ ((¬a ↓∈ as) ∧ (¬b ↓∈ bs)))


Proof




Definitions occuring in Statement :  bag-remove1: bag-remove1(eq;bs;a),  bag-member: x ↓∈ bs,  bag-append: as + bs,  single-bag: {x},  bag: bag(T),  deq: EqDecider(T),  sq_or: a ↓∨ b,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  not: ¬A,  and: P ∧ Q,  unit: Unit,  union: left + right,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  sq_or: a ↓∨ b,  squash: ↓T,  all: ∀x:A. B[x],  prop: ℙ,  or: P ∨ Q,  exists: ∃x:A. B[x],  true: True,  subtype_rel: A ⊆r B,  guard: {T},  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  not: ¬A,  false: False,  rev_implies: P ⇐ Q,  isl: isl(x),  cand: A c∧ B,  deq: EqDecider(T),  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  eqof: eqof(d),  ifthenelse: if b then t else f fi ,  outl: outl(x),  assert: ↑b,  bfalse: ff,  sq_type: SQType(T),  bnot: ¬bb,  exposed-bfalse: exposed-bfalse
Lemmas referenced :  unit_wf2,  bag-remove1_wf,  sq_or_wf,  equal_wf,  bag_wf,  bag-append_wf,  single-bag_wf,  not_wf,  bag-member_wf,  istype-universe,  bag-remove1-property,  squash_wf,  true_wf,  subtype_rel_self,  iff_weakening_equal,  istype-void,  bag-append-assoc-comm,  btrue_wf,  bfalse_wf,  btrue_neq_bfalse,  deq_wf,  bag-remove1-member,  bag-remove1-append1,  eqtt_to_assert,  safe-assert-deq,  outl_wf,  assert_wf,  isl_wf,  eqff_to_assert,  bool_cases_sqequal,  subtype_base_sq,  bool_wf,  bool_subtype_base,  assert-bnot,  iff_weakening_uiff,  bag-remove1-non-member,  bag-member-append,  bag-member-single
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  independent_pairFormation,  sqequalRule,  sqequalHypSubstitution,  imageElimination,  hypothesis,  imageMemberEquality,  hypothesisEquality,  thin,  baseClosed,  equalityIsType1,  unionIsType,  inhabitedIsType,  universeIsType,  extract_by_obid,  isectElimination,  dependent_functionElimination,  productEquality,  productElimination,  independent_pairEquality,  isect_memberEquality_alt,  because_Cache,  equalityTransitivity,  equalitySymmetry,  axiomEquality,  universeEquality,  unionElimination,  inlFormation_alt,  applyEquality,  lambdaEquality_alt,  unionEquality,  natural_numberEquality,  instantiate,  independent_isectElimination,  independent_functionElimination,  applyLambdaEquality,  productIsType,  functionIsType,  dependent_set_memberEquality_alt,  equalityIsType3,  setElimination,  rename,  voidElimination,  inrFormation_alt,  lambdaFormation_alt,  equalityElimination,  promote_hyp,  hyp_replacement,  inlEquality_alt,  dependent_pairFormation_alt,  cumulativity

Latex:
\mforall{}[T:Type].  \mforall{}[eq:EqDecider(T)].  \mforall{}[as,bs:bag(T)].  \mforall{}[a,b:T].
    uiff(bag-remove1(eq;as;a)  =  bag-remove1(eq;bs;b);((\{a\}  +  bs)  =  (\{b\}  +  as))
    \mdownarrow{}\mvee{}  ((\mneg{}a  \mdownarrow{}\mmember{}  as)  \mwedge{}  (\mneg{}b  \mdownarrow{}\mmember{}  bs)))



Date html generated: 2019_10_16-AM-11_31_14
Last ObjectModification: 2018_10_11-AM-10_46_07

Theory : bags_2


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