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: List deq: EqDecider(T) uall: [x:A]. B[x] all: x:A. B[x] iff: ⇐⇒ 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: supposing a top: Top iff: ⇐⇒ Q implies:  Q prop: rev_implies:  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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