Nuprl Lemma : longest-prefix-is-nil
∀[T:Type]. ∀[L:T List]. ∀[P:(T List) ⟶ 𝔹].
  ∀[L':T List]. (¬↑(P L')) supposing (L' < L and [] < L') supposing longest-prefix(P;L) = [] ∈ (T List)
Proof
Definitions occuring in Statement : 
longest-prefix: longest-prefix(P;L)
, 
proper-iseg: L1 < L2
, 
nil: []
, 
list: T List
, 
assert: ↑b
, 
bool: 𝔹
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
not: ¬A
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
subtype_rel: A ⊆r B
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
uimplies: b supposing a
, 
listp: A List+
, 
implies: P 
⇒ Q
, 
not: ¬A
, 
false: False
, 
and: P ∧ Q
, 
or: P ∨ Q
, 
prop: ℙ
, 
guard: {T}
Lemmas referenced : 
longest-prefix_property, 
longest-prefix_wf, 
subtype_rel_dep_function, 
list_wf, 
bool_wf, 
listp_wf, 
subtype_rel_self, 
assert_wf, 
proper-iseg_wf, 
nil_wf, 
equal-wf-T-base, 
iseg_wf, 
less_than_wf, 
length_wf, 
or_wf, 
length_of_nil_lemma, 
all_wf, 
not_wf, 
equal_wf, 
and_wf
Rules used in proof : 
cut, 
introduction, 
extract_by_obid, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
dependent_functionElimination, 
cumulativity, 
applyEquality, 
sqequalRule, 
lambdaEquality, 
independent_isectElimination, 
setElimination, 
rename, 
because_Cache, 
lambdaFormation, 
productElimination, 
unionElimination, 
functionExtensionality, 
independent_functionElimination, 
voidElimination, 
isect_memberEquality, 
equalityTransitivity, 
equalitySymmetry, 
baseClosed, 
productEquality, 
isectEquality, 
natural_numberEquality, 
applyLambdaEquality, 
functionEquality, 
universeEquality, 
hyp_replacement, 
dependent_set_memberEquality, 
independent_pairFormation
Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[P:(T  List)  {}\mrightarrow{}  \mBbbB{}].
    \mforall{}[L':T  List].  (\mneg{}\muparrow{}(P  L'))  supposing  (L'  <  L  and  []  <  L')  supposing  longest-prefix(P;L)  =  []
Date html generated:
2018_05_21-PM-06_42_04
Last ObjectModification:
2017_07_26-PM-04_54_04
Theory : general
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