Nuprl Lemma : l_tricotomy

∀[T:Type]. ∀x,y:T. ∀L:T List.  ((x ∈ L) ⇒ (y ∈ L) ⇒ (((x = y ∈ T) ∨ x before y ∈ L) ∨ y before x ∈ L))


Proof




Definitions occuring in Statement :  l_before: x before y ∈ l,  l_member: (x ∈ l),  list: T List,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  or: P ∨ Q,  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  l_before: x before y ∈ l,  l_member: (x ∈ l),  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  exists: ∃x:A. B[x],  cand: A c∧ B,  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x.t[x],  nat: ℕ,  uimplies: b supposing a,  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  not: ¬A,  top: Top,  and: P ∧ Q,  so_apply: x[s],  squash: ↓T,  sublist: L1 ⊆ L2,  int_seg: {i..j-},  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  ifthenelse: if b then t else f fi ,  uiff: uiff(P;Q),  lelt: i ≤ j < k,  le: A ≤ B,  bfalse: ff,  sq_type: SQType(T),  guard: {T},  bnot: ¬bb,  assert: ↑b,  increasing: increasing(f;k),  subtract: n - m,  nequal: a ≠ b ∈ T ,  less_than': less_than'(a;b),  subtype_rel: A ⊆r B,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  select: L[n],  cons: [a / b],  true: True
Lemmas referenced :  exists_wf,  nat_wf,  less_than_wf,  length_wf,  equal_wf,  select_wf,  nat_properties,  decidable__le,  satisfiable-full-omega-tt,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  int_formula_prop_and_lemma,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  list_wf,  decidable__lt,  sublist_wf,  cons_wf,  nil_wf,  decidable__equal_int,  squash_wf,  le_wf,  intformeq_wf,  int_formula_prop_eq_lemma,  intformless_wf,  int_formula_prop_less_lemma,  or_wf,  length_of_cons_lemma,  length_of_nil_lemma,  eq_int_wf,  bool_wf,  eqtt_to_assert,  assert_of_eq_int,  lelt_wf,  eqff_to_assert,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  neg_assert_of_eq_int,  int_seg_wf,  int_seg_properties,  itermAdd_wf,  int_term_value_add_lemma,  increasing_wf,  false_wf,  all_wf,  non_neg_length,  length_wf_nat,  equal-wf-T-base,  assert_wf,  select-cons-hd,  bnot_wf,  not_wf,  uiff_transitivity,  iff_transitivity,  iff_weakening_uiff,  assert_of_bnot,  int_subtype_base,  true_wf,  select_cons_tl,  length-singleton,  iff_weakening_equal,  subtract_wf,  itermSubtract_wf,  int_term_value_subtract_lemma
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  lambdaFormation,  sqequalHypSubstitution,  productElimination,  thin,  cut,  introduction,  extract_by_obid,  isectElimination,  hypothesis,  lambdaEquality,  productEquality,  setElimination,  rename,  because_Cache,  cumulativity,  hypothesisEquality,  independent_isectElimination,  dependent_functionElimination,  natural_numberEquality,  unionElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  universeEquality,  inlFormation,  inrFormation,  applyEquality,  imageElimination,  equalityTransitivity,  equalitySymmetry,  imageMemberEquality,  baseClosed,  equalityElimination,  dependent_set_memberEquality,  promote_hyp,  instantiate,  independent_functionElimination,  addEquality,  functionExtensionality,  applyLambdaEquality,  impliesFunctionality

Latex:
\mforall{}[T:Type].  \mforall{}x,y:T.  \mforall{}L:T  List.    ((x  \mmember{}  L)  {}\mRightarrow{}  (y  \mmember{}  L)  {}\mRightarrow{}  (((x  =  y)  \mvee{}  x  before  y  \mmember{}  L)  \mvee{}  y  before  x  \mmember{}  L))



Date html generated: 2017_04_14-AM-09_30_01
Last ObjectModification: 2017_02_27-PM-04_02_27

Theory : list_1


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