Nuprl Lemma : st-lookup-property

[T:Id ⟶ Type]
  ∀tab:secret-table(T). ∀x:Atom1.
    (↑isl(st-lookup(tab;x)) ⇐⇒ ∃n:ℕ||tab|| ((n ≤ ptr(tab)) ∧ (st-atom(tab;n) x ∈ Atom1)))


Proof




Definitions occuring in Statement :  st-lookup: st-lookup(tab;x) st-atom: st-atom(tab;n) st-ptr: ptr(tab) st-length: ||tab||  secret-table: secret-table(T) Id: Id int_seg: {i..j-} atom: Atom$n assert: b isl: isl(x) uall: [x:A]. B[x] le: A ≤ B all: x:A. B[x] exists: x:A. B[x] iff: ⇐⇒ Q and: P ∧ Q function: x:A ⟶ B[x] natural_number: $n universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] secret-table: secret-table(T) st-atom: st-atom(tab;n) st-ptr: ptr(tab) st-length: ||tab||  st-lookup: st-lookup(tab;x) spreadn: spread3 pi1: fst(t) pi2: snd(t) member: t ∈ T implies:  Q uimplies: supposing a nat: bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) and: P ∧ Q bor: p ∨bq ifthenelse: if then else fi  bfalse: ff guard: {T} int_seg: {i..j-} lelt: i ≤ j < k le: A ≤ B prop: subtype_rel: A ⊆B so_lambda: λ2x.t[x] so_apply: x[s] top: Top exists: x:A. B[x] iff: ⇐⇒ Q assert: b rev_implies:  Q or: P ∨ Q true: True ge: i ≥  satisfiable_int_formula: satisfiable_int_formula(fmla) false: False not: ¬A sq_type: SQType(T) isl: isl(x) let: let exposed-bfalse: exposed-bfalse squash: T less_than': less_than'(a;b) decidable: Dec(P) cand: c∧ B bnot: ¬bb

Latex:
\mforall{}[T:Id  {}\mrightarrow{}  Type]
    \mforall{}tab:secret-table(T).  \mforall{}x:Atom1.
        (\muparrow{}isl(st-lookup(tab;x))  \mLeftarrow{}{}\mRightarrow{}  \mexists{}n:\mBbbN{}||tab||  .  ((n  \mleq{}  ptr(tab))  \mwedge{}  (st-atom(tab;n)  =  x)))



Date html generated: 2016_05_16-AM-10_02_37
Last ObjectModification: 2016_01_17-PM-01_24_01

Theory : new!event-ordering


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