Nuprl Lemma : fpf-join-ap-sq

[A:Type]. ∀[eq:EqDecider(A)]. ∀[f:a:A fp-> Top]. ∀[g:Top]. ∀[x:A].  (f ⊕ g(x) if x ∈ dom(f) then f(x) else g(x) fi )


Proof




Definitions occuring in Statement :  fpf-join: f ⊕ g fpf-ap: f(x) fpf-dom: x ∈ dom(f) fpf: a:A fp-> B[a] deq: EqDecider(T) ifthenelse: if then else fi  uall: [x:A]. B[x] top: Top universe: Type sqequal: t
Definitions unfolded in proof :  fpf-ap: f(x) fpf-join: f ⊕ g pi2: snd(t) fpf-cap: f(x)?z member: t ∈ T uall: [x:A]. B[x] so_lambda: λ2x.t[x] so_apply: x[s] all: x:A. B[x] implies:  Q bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a ifthenelse: if then else fi  bfalse: ff prop:
Lemmas referenced :  fpf-dom_wf bool_wf equal-wf-T-base assert_wf bnot_wf not_wf top_wf fpf_wf deq_wf eqtt_to_assert uiff_transitivity eqff_to_assert assert_of_bnot equal_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity sqequalRule cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin cumulativity hypothesisEquality hypothesis because_Cache equalityTransitivity equalitySymmetry baseClosed lambdaEquality universeEquality isect_memberFormation sqequalAxiom isect_memberEquality lambdaFormation unionElimination equalityElimination productElimination independent_isectElimination independent_functionElimination dependent_functionElimination

Latex:
\mforall{}[A:Type].  \mforall{}[eq:EqDecider(A)].  \mforall{}[f:a:A  fp->  Top].  \mforall{}[g:Top].  \mforall{}[x:A].
    (f  \moplus{}  g(x)  \msim{}  if  x  \mmember{}  dom(f)  then  f(x)  else  g(x)  fi  )



Date html generated: 2018_05_21-PM-09_21_50
Last ObjectModification: 2018_02_09-AM-10_18_30

Theory : finite!partial!functions


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