Nuprl Lemma : finite-type-list

∀[T:Type]. ((∀x,y:T.  Dec(x = y ∈ T)) ⇒ (∀L:T List. finite-type({x:T| (x ∈ L)} )))


Proof




Definitions occuring in Statement :  finite-type: finite-type(T),  l_member: (x ∈ l),  list: T List,  decidable: Dec(P),  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  set: {x:A| B[x]} ,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  all: ∀x:A. B[x],  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s]
Lemmas referenced :  cardinality-le-finite,  l_member_wf,  length_wf_nat,  list_wf,  all_wf,  decidable_wf,  equal_wf,  cardinality-le-list-set
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  setEquality,  hypothesisEquality,  hypothesis,  dependent_functionElimination,  independent_functionElimination,  sqequalRule,  lambdaEquality,  universeEquality

Latex:
\mforall{}[T:Type].  ((\mforall{}x,y:T.    Dec(x  =  y))  {}\mRightarrow{}  (\mforall{}L:T  List.  finite-type(\{x:T|  (x  \mmember{}  L)\}  )))



Date html generated: 2016_05_14-PM-03_31_44
Last ObjectModification: 2015_12_26-PM-06_01_41

Theory : decidable!equality


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