Nuprl Lemma : polymorphic-choice-sq

f:⋂A:Type. (A ⟶ A ⟶ A). ((f ~ λx.if is lambda then λy.x otherwise ⊥) ∨ (f ~ λx,y. y))


Proof




Definitions occuring in Statement :  bottom: islambda: if is lambda then otherwise b all: x:A. B[x] or: P ∨ Q apply: a lambda: λx.A[x] isect: x:A. B[x] function: x:A ⟶ B[x] universe: Type sqequal: t
Definitions unfolded in proof :  member: t ∈ T uall: [x:A]. B[x] all: x:A. B[x] implies:  Q or: P ∨ Q subtype_rel: A ⊆B guard: {T} nat: le: A ≤ B and: P ∧ Q less_than': less_than'(a;b) false: False not: ¬A prop: top: Top uimplies: supposing a so_lambda: λ2x.t[x] so_apply: x[s] has-value: (a)↓ btrue: tt it: bfalse: ff ge: i ≥  exists: x:A. B[x] satisfiable_int_formula: satisfiable_int_formula(fmla) decidable: Dec(P) squash: T iff: ⇐⇒ Q rev_implies:  Q true: True sq_type: SQType(T)
Lemmas referenced :  istype-universe polymorphic-choice-base-sq nat_wf false_wf le_wf top_wf value-type-has-value set-value-type int-value-type has-value_wf_base is-exception_wf set_subtype_base int_subtype_base equal_wf strictness-apply bottom_diverge int_term_value_var_lemma int_formula_prop_and_lemma itermVar_wf intformand_wf nat_properties istype-le int_formula_prop_wf int_term_value_constant_lemma int_formula_prop_le_lemma istype-void int_formula_prop_not_lemma istype-int itermConstant_wf intformle_wf intformnot_wf full-omega-unsat decidable__le equal_functionality_wrt_subtype_rel2 istype-top decidable__equal_int intformeq_wf int_formula_prop_eq_lemma true_wf squash_wf member_wf istype-sqequal not_zero_sqequal_one iff_weakening_equal subtype_rel_self istype-base subtype_base_sq equal-wf-base or_wf sqequal-wf-base
Rules used in proof :  because_Cache hypothesisEquality Error :universeIsType,  Error :functionIsType,  hypothesis universeEquality thin isectElimination sqequalHypSubstitution extract_by_obid introduction instantiate cut Error :isectIsType,  Error :lambdaFormation_alt,  sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution pointwiseFunctionality dependent_functionElimination independent_functionElimination equalityTransitivity equalitySymmetry unionElimination sqequalRule applyEquality lambdaEquality isectEquality cumulativity functionEquality dependent_set_memberEquality natural_numberEquality independent_pairFormation lambdaFormation islambdaCases isect_memberFormation axiomSqEquality isect_memberEquality voidElimination voidEquality independent_isectElimination intEquality functionExtensionality callbyvalueApply divergentSqle baseClosed baseApply closedConclusion inlEquality sqequalIntensionalEquality inrEquality Error :equalityIstype,  int_eqEquality rename setElimination applyLambdaEquality Error :isect_memberEquality_alt,  Error :dependent_pairFormation_alt,  approximateComputation Error :dependent_set_memberEquality_alt,  Error :inhabitedIsType,  Error :lambdaEquality_alt,  Error :isectIsTypeImplies,  Error :isect_memberFormation_alt,  int_eqReduceTrueSq imageMemberEquality imageElimination unionEquality sqequalExtensionalEquality Error :inlEquality_alt,  productElimination callbyvalueIslambda

Latex:
\mforall{}f:\mcap{}A:Type.  (A  {}\mrightarrow{}  A  {}\mrightarrow{}  A).  ((f  \msim{}  \mlambda{}x.if  f  x  is  lambda  then  \mlambda{}y.x  otherwise  \mbot{})  \mvee{}  (f  \msim{}  \mlambda{}x,y.  y))



Date html generated: 2019_06_20-PM-02_45_22
Last ObjectModification: 2019_01_09-PM-03_39_35

Theory : num_thy_1


Home Index