Nuprl Lemma : csm-discrete-pi
∀[A:Type]. ∀[B:A ⟶ Type]. ∀[X,Y:j⊢]. ∀[s:Y j⟶ X].
  ((Πdiscr(A) discrete-family(A;a.B[a]))s = Y ⊢ Πdiscr(A) discrete-family(A;a.B[a]) ∈ {Y ⊢ _})
Proof
Definitions occuring in Statement : 
discrete-family: discrete-family(A;a.B[a])
, 
discrete-cubical-type: discr(T)
, 
cubical-pi: ΠA B
, 
csm-ap-type: (AF)s
, 
cubical-type: {X ⊢ _}
, 
cube_set_map: A ⟶ B
, 
cubical_set: CubicalSet
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
function: x:A ⟶ B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
member: t ∈ T
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
discrete-cubical-type: discr(T)
, 
csm-ap-type: (AF)s
, 
discrete-family: discrete-family(A;a.B[a])
, 
cc-snd: q
, 
cc-fst: p
, 
csm-comp: G o F
, 
csm-adjoin: (s;u)
, 
compose: f o g
, 
csm-ap: (s)x
, 
pi2: snd(t)
Lemmas referenced : 
csm-cubical-pi, 
discrete-cubical-type_wf, 
discrete-family_wf, 
cube_set_map_wf, 
cubical_set_wf, 
istype-universe
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
hypothesisEquality, 
isectElimination, 
hypothesis, 
sqequalRule, 
lambdaEquality_alt, 
applyEquality, 
universeIsType, 
because_Cache, 
instantiate, 
functionIsType, 
inhabitedIsType, 
universeEquality
Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[X,Y:j\mvdash{}].  \mforall{}[s:Y  j{}\mrightarrow{}  X].
    ((\mPi{}discr(A)  discrete-family(A;a.B[a]))s  =  Y  \mvdash{}  \mPi{}discr(A)  discrete-family(A;a.B[a]))
Date html generated:
2020_05_20-PM-03_38_23
Last ObjectModification:
2020_04_07-PM-04_28_56
Theory : cubical!type!theory
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