Nuprl Lemma : fun-path-append

∀[T:Type]. ∀[f:T ⟶ T]. ∀[L1,L2:T List]. ∀[x,y,z:T].
  uiff(z=f*(x) via L1 @ [y / L2];{y=f*(x) via [y / L2] ∧ z=f*(y) via L1 @ [y]})


Proof




Definitions occuring in Statement :  fun-path: y=f*(x) via L,  append: as @ bs,  cons: [a / b],  nil: [],  list: T List,  uiff: uiff(P;Q),  uall: ∀[x:A]. B[x],  guard: {T},  and: P ∧ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  subtype_rel: A ⊆r B,  decidable: Dec(P),  so_apply: x[s1;s2],  so_lambda: λ2x y.t[x; y],  squash: ↓T,  less_than: a < b,  sq_type: SQType(T),  so_apply: x[s],  so_lambda: λ2x.t[x],  it: ⋅,  nil: [],  colength: colength(L),  less_than': less_than'(a;b),  le: A ≤ B,  cons: [a / b],  or: P ∨ Q,  fun-path: y=f*(x) via L,  guard: {T},  uiff: uiff(P;Q),  prop: ℙ,  and: P ∧ Q,  top: Top,  exists: ∃x:A. B[x],  satisfiable_int_formula: satisfiable_int_formula(fmla),  not: ¬A,  uimplies: b supposing a,  ge: i ≥ j ,  false: False,  implies: P ⇒ Q,  nat: ℕ,  all: ∀x:A. B[x],  member: t ∈ T,  uall: ∀[x:A]. B[x],  so_apply: x[s1;s2;s3],  so_lambda: so_lambda3,  append: as @ bs,  subtract: n - m,  last: last(L),  select: L[n],  cand: A c∧ B,  true: True,  int_seg: {i..j-},  lelt: i ≤ j < k,  nat_plus: ℕ+,  listp: A List+,  rev_implies: P ⇐ Q,  iff: P ⇐⇒ Q
Lemmas referenced :  list_wf,  nat_wf,  decidable__le,  int_term_value_add_lemma,  int_term_value_subtract_lemma,  int_formula_prop_not_lemma,  itermAdd_wf,  itermSubtract_wf,  intformnot_wf,  subtract_wf,  decidable__equal_int,  spread_cons_lemma,  int_subtype_base,  set_subtype_base,  subtype_base_sq,  subtract-1-ge-0,  istype-universe,  fun-path_wf,  nil_wf,  append_wf,  cons_wf,  length_wf,  le_wf,  istype-false,  colength_wf_list,  colength-cons-not-zero,  product_subtype_list,  list-cases,  length_of_nil_lemma,  length-append,  int_formula_prop_eq_lemma,  intformeq_wf,  length_of_cons_lemma,  member-less_than,  less_than_wf,  ge_wf,  int_formula_prop_wf,  int_formula_prop_less_lemma,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_le_lemma,  istype-void,  int_formula_prop_and_lemma,  istype-int,  intformless_wf,  itermVar_wf,  itermConstant_wf,  intformle_wf,  intformand_wf,  full-omega-unsat,  nat_properties,  reduce_hd_cons_lemma,  list_ind_nil_lemma,  int_seg_properties,  int_seg_wf,  list_ind_cons_lemma,  fun-path-cons,  false_wf,  add-is-int-iff,  decidable__lt,  nat_plus_properties,  length_wf_nat,  add_nat_plus,  listp_properties,  hd_wf,  top_wf,  subtype_rel_list,  length_append,  length_cons,  non_neg_length,  length_nil,  not_wf,  equal_wf,  iff_weakening_uiff
Rules used in proof :  universeEquality,  functionIsType,  intEquality,  applyEquality,  baseClosed,  closedConclusion,  baseApply,  equalityIsType4,  imageElimination,  instantiate,  productEquality,  dependent_set_memberEquality_alt,  because_Cache,  equalityIsType1,  hypothesis_subsumption,  promote_hyp,  unionElimination,  inhabitedIsType,  functionIsTypeImplies,  axiomEquality,  applyLambdaEquality,  equalitySymmetry,  equalityTransitivity,  independent_pairEquality,  productElimination,  universeIsType,  independent_pairFormation,  sqequalRule,  voidElimination,  isect_memberEquality_alt,  dependent_functionElimination,  int_eqEquality,  lambdaEquality_alt,  dependent_pairFormation_alt,  independent_functionElimination,  approximateComputation,  independent_isectElimination,  natural_numberEquality,  intWeakElimination,  rename,  setElimination,  hypothesis,  hypothesisEquality,  isectElimination,  sqequalHypSubstitution,  extract_by_obid,  lambdaFormation_alt,  thin,  cut,  introduction,  isect_memberFormation_alt,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  productIsType,  hyp_replacement,  Error :memTop,  imageMemberEquality,  pointwiseFunctionality,  voidEquality,  isectEquality,  addEquality

Latex:
\mforall{}[T:Type].  \mforall{}[f:T  {}\mrightarrow{}  T].  \mforall{}[L1,L2:T  List].  \mforall{}[x,y,z:T].
    uiff(z=f*(x)  via  L1  @  [y  /  L2];\{y=f*(x)  via  [y  /  L2]  \mwedge{}  z=f*(y)  via  L1  @  [y]\})



Date html generated: 2020_05_20-AM-08_10_23
Last ObjectModification: 2020_01_17-AM-11_35_29

Theory : general


Home Index