Nuprl Lemma : has-value-is-list-approx-is-type

[T:Type]. ∀[t:colist(T)]. ∀[n:ℕ].
  ((λis-list,t. eval in if is pair then is-list (snd(u)) otherwise if Ax then tt otherwise ⊥^n ⊥ t)↓ ∈ Typ\000Ce)


Proof




Definitions occuring in Statement :  colist: colist(T) fun_exp: f^n nat: has-value: (a)↓ callbyvalue: callbyvalue bottom: btrue: tt uall: [x:A]. B[x] pi2: snd(t) ispair: if is pair then otherwise b isaxiom: if Ax then otherwise b member: t ∈ T apply: a lambda: λx.A[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T nat: implies:  Q false: False ge: i ≥  uimplies: supposing a not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] all: x:A. B[x] top: Top and: P ∧ Q prop: decidable: Dec(P) or: P ∨ Q bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) ifthenelse: if then else fi  bfalse: ff sq_type: SQType(T) guard: {T} bnot: ¬bb assert: b compose: g has-value: (a)↓ pi2: snd(t) ext-eq: A ≡ B
Lemmas referenced :  nat_properties full-omega-unsat intformand_wf intformle_wf itermConstant_wf itermVar_wf intformless_wf istype-int int_formula_prop_and_lemma istype-void int_formula_prop_le_lemma int_term_value_constant_lemma int_term_value_var_lemma int_formula_prop_less_lemma int_formula_prop_wf ge_wf istype-less_than fun_exp0_lemma strictness-apply has-value_wf_base subtract-1-ge-0 fun_exp_unroll decidable__le intformnot_wf int_formula_prop_not_lemma istype-le eq_int_wf eqtt_to_assert assert_of_eq_int intformeq_wf int_formula_prop_eq_lemma eqff_to_assert bool_cases_sqequal subtype_base_sq bool_wf bool_subtype_base assert-bnot neg_assert_of_eq_int value-type-has-value colist_wf colist-value-type co-list-cases unit_subtype_colist sqle_wf_base subtype_rel_transitivity b-union_wf unit_wf2 subtype_rel_b-union-right colist-ext istype-nat istype-universe
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut thin extract_by_obid sqequalHypSubstitution isectElimination hypothesisEquality hypothesis setElimination rename sqequalRule intWeakElimination lambdaFormation_alt natural_numberEquality independent_isectElimination approximateComputation independent_functionElimination dependent_pairFormation_alt lambdaEquality_alt int_eqEquality dependent_functionElimination isect_memberEquality_alt voidElimination independent_pairFormation universeIsType axiomEquality equalityTransitivity equalitySymmetry functionIsTypeImplies inhabitedIsType baseClosed because_Cache dependent_set_memberEquality_alt unionElimination equalityElimination productElimination equalityIstype promote_hyp instantiate cumulativity callbyvalueReduce hypothesis_subsumption productEquality isectIsTypeImplies universeEquality

Latex:
\mforall{}[T:Type].  \mforall{}[t:colist(T)].  \mforall{}[n:\mBbbN{}].
    ((\mlambda{}is-list,t.  eval  u  =  t  in
                                if  u  is  a  pair  then  is-list  (snd(u))  otherwise  if  u  =  Ax  then  tt  otherwise  \mbot{}\^{}n 
        \mbot{} 
        t)\mdownarrow{}  \mmember{}  Type)



Date html generated: 2019_10_16-AM-11_38_22
Last ObjectModification: 2019_06_26-PM-05_07_14

Theory : eval!all


Home Index