Nuprl Lemma : list-to-set-property

∀[T:Type]
  ∀eq:EqDecider(T). ∀L:T List.  (no_repeats(T;list-to-set(eq;L)) ∧ (∀a:T. ((a ∈ list-to-set(eq;L)) ⇐⇒ (a ∈ L))))


Proof




Definitions occuring in Statement :  list-to-set: list-to-set(eq;L),  no_repeats: no_repeats(T;l),  l_member: (x ∈ l),  list: T List,  deq: EqDecider(T),  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  list-to-set: list-to-set(eq;L),  and: P ∧ Q,  member: t ∈ T,  uimplies: b supposing a,  top: Top,  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  prop: ℙ,  rev_implies: P ⇐ Q,  or: P ∨ Q,  not: ¬A,  false: False,  guard: {T}
Lemmas referenced :  no_repeats_union,  nil_wf,  no_repeats_nil,  member-union,  l_member_wf,  l-union_wf,  iff_wf,  or_wf,  list_wf,  deq_wf,  null_nil_lemma,  btrue_wf,  member-implies-null-eq-bfalse,  btrue_neq_bfalse
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  independent_pairFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  independent_isectElimination,  isect_memberEquality,  voidElimination,  voidEquality,  addLevel,  productElimination,  impliesFunctionality,  because_Cache,  dependent_functionElimination,  independent_functionElimination,  universeEquality,  unionElimination,  sqequalRule,  equalityTransitivity,  equalitySymmetry,  inrFormation

Latex:
\mforall{}[T:Type]
    \mforall{}eq:EqDecider(T).  \mforall{}L:T  List.
        (no\_repeats(T;list-to-set(eq;L))  \mwedge{}  (\mforall{}a:T.  ((a  \mmember{}  list-to-set(eq;L))  \mLeftarrow{}{}\mRightarrow{}  (a  \mmember{}  L))))



Date html generated: 2018_05_21-PM-00_51_14
Last ObjectModification: 2018_05_19-AM-06_40_51

Theory : decidable!equality


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