Nuprl Lemma : l_before_append_iff

∀[T:Type]. ∀A,B:T List. ∀x,y:T.  (x before y ∈ A @ B ⇐⇒ x before y ∈ A ∨ x before y ∈ B ∨ ((x ∈ A) ∧ (y ∈ B)))


Proof




Definitions occuring in Statement :  l_before: x before y ∈ l,  l_member: (x ∈ l),  append: as @ bs,  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  or: P ∨ Q,  and: P ∧ Q,  universe: Type
Definitions unfolded in proof :  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  so_apply: x[s],  and: P ∧ Q,  or: P ∨ Q,  prop: ℙ,  so_lambda: λ2x.t[x],  member: t ∈ T,  all: ∀x:A. B[x],  uall: ∀[x:A]. B[x],  append: as @ bs,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  top: Top,  so_apply: x[s1;s2;s3],  guard: {T},  uimplies: b supposing a,  not: ¬A,  false: False,  cand: A c∧ B
Lemmas referenced :  istype-universe,  l_member_wf,  append_wf,  l_before_wf,  iff_wf,  list_wf,  list_induction,  list_ind_nil_lemma,  nil_wf,  or_wf,  null_nil_lemma,  btrue_wf,  member-implies-null-eq-bfalse,  btrue_neq_bfalse,  nil_before,  cons_wf,  list_ind_cons_lemma,  istype-void,  cons_before,  cons_member,  member_append
Rules used in proof :  universeEquality,  instantiate,  dependent_functionElimination,  unionIsType,  productIsType,  because_Cache,  functionIsType,  rename,  independent_functionElimination,  universeIsType,  productEquality,  unionEquality,  hypothesis,  functionEquality,  lambdaEquality_alt,  sqequalRule,  hypothesisEquality,  isectElimination,  sqequalHypSubstitution,  extract_by_obid,  introduction,  thin,  cut,  lambdaFormation_alt,  isect_memberFormation_alt,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  isect_memberEquality,  voidElimination,  voidEquality,  lambdaFormation,  independent_pairFormation,  inrFormation,  inlFormation,  cumulativity,  unionElimination,  productElimination,  independent_isectElimination,  equalityTransitivity,  equalitySymmetry,  inhabitedIsType,  equalityIstype,  isect_memberEquality_alt,  inlFormation_alt,  inrFormation_alt,  promote_hyp

Latex:
\mforall{}[T:Type]
    \mforall{}A,B:T  List.  \mforall{}x,y:T.
        (x  before  y  \mmember{}  A  @  B  \mLeftarrow{}{}\mRightarrow{}  x  before  y  \mmember{}  A  \mvee{}  x  before  y  \mmember{}  B  \mvee{}  ((x  \mmember{}  A)  \mwedge{}  (y  \mmember{}  B)))



Date html generated: 2019_10_15-AM-10_21_41
Last ObjectModification: 2019_08_05-PM-02_08_48

Theory : list_1


Home Index