Nuprl Lemma : single-valued-bag-hd

∀[T:Type]. ∀[b:bag(T)].  (hd(b) ∈ T) supposing (0 < #(b) and single-valued-bag(b;T))


Proof




Definitions occuring in Statement :  single-valued-bag: single-valued-bag(b;T),  bag-size: #(bs),  bag: bag(T),  hd: hd(l),  less_than: a < b,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  member: t ∈ T,  natural_number: $n,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  bag: bag(T),  all: ∀x:A. B[x],  prop: ℙ,  quotient: x,y:A//B[x; y],  and: P ∧ Q,  bag-size: #(bs),  listp: A List+,  squash: ↓T,  true: True,  subtype_rel: A ⊆r B,  nat: ℕ,  permutation: permutation(T;L1;L2),  exists: ∃x:A. B[x],  top: Top,  le: A ≤ B,  less_than': less_than'(a;b),  false: False,  not: ¬A,  implies: P ⇒ Q,  int_seg: {i..j-},  lelt: i ≤ j < k,  guard: {T},  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  single-valued-bag: single-valued-bag(b;T),  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  so_lambda: λ2x.t[x],  so_apply: x[s]
Lemmas referenced :  list_wf,  permutation_wf,  permutation_weakening,  hd_wf,  listp_properties,  less_than_wf,  length_wf,  equal-wf-base,  member_wf,  squash_wf,  true_wf,  bag-size_wf,  nat_wf,  single-valued-bag_wf,  bag_wf,  permutation-length,  length_wf_nat,  equal_wf,  select0,  select_wf,  false_wf,  permute_list_select,  lelt_wf,  subtype_rel_self,  iff_weakening_equal,  int_seg_wf,  non_neg_length,  decidable__le,  nat_properties,  int_seg_properties,  full-omega-unsat,  intformand_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  intformnot_wf,  int_formula_prop_and_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_not_lemma,  int_formula_prop_wf,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  bag-member-select,  subtype_rel_sets,  less_than_transitivity1,  le_weakening
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalHypSubstitution,  extract_by_obid,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  promote_hyp,  lambdaFormation,  equalityTransitivity,  equalitySymmetry,  because_Cache,  dependent_functionElimination,  independent_isectElimination,  pointwiseFunctionality,  sqequalRule,  pertypeElimination,  productElimination,  cumulativity,  dependent_set_memberEquality,  natural_numberEquality,  productEquality,  applyEquality,  lambdaEquality,  imageElimination,  imageMemberEquality,  baseClosed,  axiomEquality,  setElimination,  rename,  isect_memberEquality,  universeEquality,  voidElimination,  voidEquality,  independent_pairFormation,  instantiate,  independent_functionElimination,  functionExtensionality,  unionElimination,  applyLambdaEquality,  approximateComputation,  dependent_pairFormation,  int_eqEquality,  intEquality,  hyp_replacement,  setEquality

Latex:
\mforall{}[T:Type].  \mforall{}[b:bag(T)].    (hd(b)  \mmember{}  T)  supposing  (0  <  \#(b)  and  single-valued-bag(b;T))



Date html generated: 2018_05_21-PM-06_24_57
Last ObjectModification: 2018_05_19-PM-05_15_26

Theory : bags


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