Nuprl Lemma : discrete-fun-app-invariant

[A,B:Type]. ∀[f:{() ⊢ _:(discr(A) ⟶ discr(B))}]. ∀[I:fset(ℕ)]. ∀[a:()(I)]. ∀[t:A].
  (app(f; discr(t))(a) app(f; discr(t))(⋅) ∈ B)


Proof




Definitions occuring in Statement :  discrete-cubical-term: discr(t) discrete-cubical-type: discr(T) cubical-app: app(w; u) cubical-fun: (A ⟶ B) cubical-term-at: u(a) cubical-term: {X ⊢ _:A} trivial-cube-set: () I_cube: A(I) empty-fset: {} fset: fset(T) nat: it: uall: [x:A]. B[x] universe: Type equal: t ∈ T
Definitions unfolded in proof :  cubical-term-at: u(a) uall: [x:A]. B[x] member: t ∈ T discrete-cubical-term: discr(t) cubical-app: app(w; u) discrete-cubical-type: discr(T) cubical-fun: (A ⟶ B) all: x:A. B[x] top: Top cubical-fun-family: cubical-fun-family(X; A; B; I; a) squash: T cubical-term: {X ⊢ _:A} subtype_rel: A ⊆B unit: Unit I_cube: A(I) functor-ob: ob(F) pi1: fst(t) trivial-cube-set: () prop: implies:  Q names-hom: I ⟶ J names: names(I) false: False true: True cubical-type-at: A(a) so_lambda: λ2x.t[x] so_apply: x[s] uimplies: supposing a guard: {T}
Lemmas referenced :  discrete-fun-invariant I_cube_wf trivial-cube-set_wf fset_wf nat_wf cubical-term_wf cubical-fun_wf discrete-cubical-type_wf cubical_type_at_pair_lemma cubical_type_ap_morph_pair_lemma empty-fset_wf it_wf subtype_rel_self equal-wf-base cubical-type-at_wf equal_wf dM0_wf names_wf member-empty-fset squash_wf true_wf nh-id_wf subtype_rel_dep_function names-hom_wf cube-set-restriction_wf equal_functionality_wrt_subtype_rel2
Rules used in proof :  sqequalSubstitution sqequalRule sqequalReflexivity sqequalTransitivity computationStep cut introduction extract_by_obid isect_memberFormation hypothesis sqequalHypSubstitution isectElimination thin hypothesisEquality cumulativity universeEquality dependent_functionElimination isect_memberEquality voidElimination voidEquality applyLambdaEquality setElimination rename imageMemberEquality baseClosed imageElimination applyEquality functionExtensionality intEquality because_Cache lambdaFormation equalityTransitivity equalitySymmetry independent_functionElimination lambdaEquality hyp_replacement natural_numberEquality functionEquality independent_isectElimination

Latex:
\mforall{}[A,B:Type].  \mforall{}[f:\{()  \mvdash{}  \_:(discr(A)  {}\mrightarrow{}  discr(B))\}].  \mforall{}[I:fset(\mBbbN{})].  \mforall{}[a:()(I)].  \mforall{}[t:A].
    (app(f;  discr(t))(a)  =  app(f;  discr(t))(\mcdot{}))



Date html generated: 2017_10_05-AM-02_12_20
Last ObjectModification: 2017_03_02-PM-11_21_26

Theory : cubical!type!theory


Home Index