Nuprl Lemma : finite-type-union

∀[A,B:Type].  (finite-type(A) ⇒ finite-type(B) ⇒ finite-type(A + B))


Proof




Definitions occuring in Statement :  finite-type: finite-type(T),  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  union: left + right,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  member: t ∈ T,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  exists: ∃x:A. B[x],  all: ∀x:A. B[x],  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  or: P ∨ Q,  cand: A c∧ B,  guard: {T}
Lemmas referenced :  finite-type-iff-list,  append_wf,  map_wf,  member_append,  member_map,  l_member_wf,  or_wf,  exists_wf,  and_wf,  equal_wf,  all_wf,  finite-type_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  productElimination,  independent_functionElimination,  unionEquality,  dependent_pairFormation,  lambdaEquality,  inlEquality,  inrEquality,  because_Cache,  dependent_functionElimination,  addLevel,  orFunctionality,  sqequalRule,  universeEquality,  unionElimination,  inlFormation,  independent_pairFormation,  inrFormation

Latex:
\mforall{}[A,B:Type].    (finite-type(A)  {}\mRightarrow{}  finite-type(B)  {}\mRightarrow{}  finite-type(A  +  B))



Date html generated: 2016_05_15-PM-04_26_24
Last ObjectModification: 2015_12_27-PM-02_51_16

Theory : general


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