Nuprl Lemma : inl-do-apply

∀[A,B:Type]. ∀[f:A ⟶ (B + Top)]. ∀[x:A].  inl do-apply(f;x) ~ f x supposing ↑can-apply(f;x)


Proof




Definitions occuring in Statement :  do-apply: do-apply(f;x),  can-apply: can-apply(f;x),  assert: ↑b,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  top: Top,  apply: f a,  function: x:A ⟶ B[x],  inl: inl x,  union: left + right,  universe: Type,  sqequal: s ~ t
Definitions unfolded in proof :  do-apply: do-apply(f;x),  can-apply: can-apply(f;x),  member: t ∈ T,  all: ∀x:A. B[x],  implies: P ⇒ Q,  isl: isl(x),  outl: outl(x),  assert: ↑b,  ifthenelse: if b then t else f fi ,  btrue: tt,  prop: ℙ,  bfalse: ff,  false: False,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  uimplies: b supposing a,  top: Top
Lemmas referenced :  top_wf,  true_wf,  false_wf,  equal_wf,  assert_wf,  can-apply_wf,  subtype_rel_union
Rules used in proof :  cut,  thin,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  applyEquality,  functionExtensionality,  hypothesisEquality,  cumulativity,  unionEquality,  introduction,  extract_by_obid,  hypothesis,  lambdaFormation,  unionElimination,  sqequalRule,  sqequalHypSubstitution,  voidElimination,  isectElimination,  equalityTransitivity,  equalitySymmetry,  dependent_functionElimination,  independent_functionElimination,  because_Cache,  independent_isectElimination,  lambdaEquality,  isect_memberEquality,  voidEquality,  functionEquality,  universeEquality,  isect_memberFormation,  sqequalAxiom

Latex:
\mforall{}[A,B:Type].  \mforall{}[f:A  {}\mrightarrow{}  (B  +  Top)].  \mforall{}[x:A].    inl  do-apply(f;x)  \msim{}  f  x  supposing  \muparrow{}can-apply(f;x)



Date html generated: 2017_10_01-AM-09_13_17
Last ObjectModification: 2017_07_26-PM-04_48_45

Theory : general


Home Index