Nuprl Lemma : apply-ifthenelse-pi2

∀[T1,U1,T2,U2:Type]. ∀[x:T1 × U1]. ∀[y:T2 × U2]. ∀[b:𝔹].
  (snd(if b then x else y fi ) ~ if b then snd(x) else snd(y) fi )


Proof




Definitions occuring in Statement :  ifthenelse: if b then t else f fi ,  bool: 𝔹,  uall: ∀[x:A]. B[x],  pi2: snd(t),  product: x:A × B[x],  universe: Type,  sqequal: s ~ t
Definitions unfolded in proof :  bool: 𝔹,  ifthenelse: if b then t else f fi ,  member: t ∈ T,  uall: ∀[x:A]. B[x]
Lemmas referenced :  bool_wf
Rules used in proof :  sqequalHypSubstitution,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  unionElimination,  thin,  sqequalRule,  cut,  lemma_by_obid,  hypothesis,  because_Cache,  productEquality,  hypothesisEquality,  universeEquality,  isect_memberFormation,  introduction,  sqequalAxiom,  isect_memberEquality,  isectElimination

Latex:
\mforall{}[T1,U1,T2,U2:Type].  \mforall{}[x:T1  \mtimes{}  U1].  \mforall{}[y:T2  \mtimes{}  U2].  \mforall{}[b:\mBbbB{}].
    (snd(if  b  then  x  else  y  fi  )  \msim{}  if  b  then  snd(x)  else  snd(y)  fi  )



Date html generated: 2016_05_13-PM-04_01_36
Last ObjectModification: 2015_12_26-AM-10_49_16

Theory : bool_1


Home Index