Nuprl Lemma : sqle-append-nil-if-has-value
∀[t:Base]. t ≤ t @ [] supposing (t)↓ 
⇒ (is-list(t))↓
Proof
Definitions occuring in Statement : 
is-list: is-list(t)
, 
append: as @ bs
, 
nil: []
, 
has-value: (a)↓
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
implies: P 
⇒ Q
, 
base: Base
, 
sqle: s ≤ t
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
member: t ∈ T
, 
append: as @ bs
, 
list_ind: list_ind, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
uimplies: b supposing a
, 
is-list: is-list(t)
, 
sq_stable: SqStable(P)
, 
nat: ℕ
, 
false: False
, 
ge: i ≥ j 
, 
not: ¬A
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
exists: ∃x:A. B[x]
, 
top: Top
, 
and: P ∧ Q
, 
subtype_rel: A ⊆r B
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
nat_plus: ℕ+
, 
has-value: (a)↓
, 
cons: [a / b]
, 
so_lambda: so_lambda(x,y,z.t[x; y; z])
, 
so_apply: x[s1;s2;s3]
, 
pi2: snd(t)
, 
it: ⋅
, 
nil: []
, 
squash: ↓T
, 
guard: {T}
Lemmas referenced : 
has-value_wf_base, 
is-exception_wf, 
base_wf, 
sq_stable__sqle, 
nat_properties, 
full-omega-unsat, 
intformand_wf, 
intformle_wf, 
itermConstant_wf, 
itermVar_wf, 
intformless_wf, 
int_formula_prop_and_lemma, 
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, 
less_than_wf, 
int_subtype_base, 
fun_exp0_lemma, 
strictness-apply, 
bottom_diverge, 
decidable__le, 
subtract_wf, 
intformnot_wf, 
itermSubtract_wf, 
int_formula_prop_not_lemma, 
int_term_value_subtract_lemma, 
fun_exp_unroll_1, 
has-value-implies-dec-ispair, 
list_ind_cons_lemma, 
has-value-implies-dec-isaxiom, 
list_ind_nil_lemma
Rules used in proof : 
cut, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
introduction, 
exceptionSqequal, 
hypothesis, 
axiomSqleEquality, 
sqequalRule, 
divergentSqle, 
sqleReflexivity, 
thin, 
instantiate, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
baseApply, 
closedConclusion, 
baseClosed, 
hypothesisEquality, 
isect_memberFormation, 
independent_functionElimination, 
compactness, 
setElimination, 
rename, 
intWeakElimination, 
natural_numberEquality, 
independent_isectElimination, 
approximateComputation, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
dependent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
independent_pairFormation, 
applyEquality, 
because_Cache, 
unionElimination, 
dependent_set_memberEquality, 
callbyvalueReduce, 
sqleRule, 
imageMemberEquality, 
imageElimination, 
functionEquality, 
equalityTransitivity, 
equalitySymmetry
Latex:
\mforall{}[t:Base].  t  \mleq{}  t  @  []  supposing  (t)\mdownarrow{}  {}\mRightarrow{}  (is-list(t))\mdownarrow{}
Date html generated:
2019_10_16-AM-11_38_07
Last ObjectModification:
2018_08_15-PM-03_49_28
Theory : eval!all
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