Nuprl Lemma : mapfilter-no-rep-fun

∀[T,U,V:Type]. ∀[eq:EqDecider(U)]. ∀[L:T List]. ∀[u:U]. ∀[f:T ⟶ U]. ∀[g:{x:{x:T| (x ∈ L)} | ↑(eq f[x] u)}  ⟶ V].
  ||mapfilter(g;λx.(eq f[x] u);L)|| ≤ 1 supposing no_repeats(U;map(f;L))


Proof




Definitions occuring in Statement :  mapfilter: mapfilter(f;P;L),  no_repeats: no_repeats(T;l),  l_member: (x ∈ l),  length: ||as||,  map: map(f;as),  list: T List,  deq: EqDecider(T),  assert: ↑b,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  so_apply: x[s],  le: A ≤ B,  set: {x:A| B[x]} ,  apply: f a,  lambda: λx.A[x],  function: x:A ⟶ B[x],  natural_number: $n,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  deq: EqDecider(T),  so_apply: x[s],  subtype_rel: A ⊆r B,  prop: ℙ,  so_lambda: λ2x.t[x],  and: P ∧ Q,  uimplies: b supposing a,  all: ∀x:A. B[x],  implies: P ⇒ Q,  cand: A c∧ B,  decidable: Dec(P),  or: P ∨ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  not: ¬A,  top: Top,  le: A ≤ B,  mapfilter: mapfilter(f;P;L),  true: True,  squash: ↓T,  guard: {T},  iff: P ⇐⇒ Q,  eqof: eqof(d),  uiff: uiff(P;Q),  less_than': less_than'(a;b),  int_seg: {i..j-},  lelt: i ≤ j < k,  less_than: a < b,  l_before: x before y ∈ l,  sublist: L1 ⊆ L2,  select: L[n],  cons: [a / b],  subtract: n - m,  no_repeats: no_repeats(T;l),  ge: i ≥ j ,  nat: ℕ,  increasing: increasing(f;k)
Lemmas referenced :  length_wf,  mapfilter-wf,  subtype_rel_dep_function,  l_member_wf,  assert_wf,  subtype_rel_sets,  set_wf,  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,  less_than'_wf,  no_repeats_wf,  map_wf,  list_wf,  deq_wf,  length-map,  filter_wf5,  filter_is_sublist,  sublist_wf,  equal_wf,  squash_wf,  true_wf,  iff_weakening_equal,  member_filter_2,  safe-assert-deq,  select_wf,  false_wf,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  select_member,  lelt_wf,  l_before_sublist,  l_before_select,  le_wf,  length_of_cons_lemma,  length_of_nil_lemma,  int_seg_wf,  map-length,  non_neg_length,  length_wf_nat,  nat_properties,  int_seg_properties,  nat_wf,  subtype_rel_list,  top_wf,  select-map,  intformeq_wf,  int_formula_prop_eq_lemma
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isectElimination,  thin,  hypothesisEquality,  because_Cache,  lambdaEquality,  applyEquality,  setElimination,  rename,  hypothesis,  functionExtensionality,  cumulativity,  sqequalRule,  setEquality,  productEquality,  independent_isectElimination,  lambdaFormation,  productElimination,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  natural_numberEquality,  unionElimination,  dependent_pairFormation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality,  independent_pairFormation,  computeAll,  functionEquality,  universeEquality,  isect_memberFormation,  independent_pairEquality,  axiomEquality,  imageElimination,  imageMemberEquality,  baseClosed,  independent_functionElimination,  dependent_set_memberEquality,  hyp_replacement,  applyLambdaEquality

Latex:
\mforall{}[T,U,V:Type].  \mforall{}[eq:EqDecider(U)].  \mforall{}[L:T  List].  \mforall{}[u:U].  \mforall{}[f:T  {}\mrightarrow{}  U].  \mforall{}[g:\{x:\{x:T|  (x  \mmember{}  L)\}  | 
                                                                                                                                                    \muparrow{}(eq  f[x]  u)\}    {}\mrightarrow{}  V].
    ||mapfilter(g;\mlambda{}x.(eq  f[x]  u);L)||  \mleq{}  1  supposing  no\_repeats(U;map(f;L))



Date html generated: 2017_09_29-PM-06_04_32
Last ObjectModification: 2017_07_26-PM-02_53_05

Theory : decidable!equality


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