[Imprint][Data Privacy Statement][E-Mail]



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Proof step 1 from proof lastwrite-to-update (conclusion) (back to tree)

⊦ (h2 |W | l) | true = [] → mem ⊕ (h1 + (W(t, l, v), b) ' + (h2 | true)) = (mem ⊕ (h1 + (h2 | true)))(l := v)

System applied rule normalize

And obtained the following new goals

Rule argument

Additional information

Proof step 2 from proof lastwrite-to-update (previous step) (back to tree)

(h2 |W | l) | true = [], mem ⊕ (h1 + (W(t, l, v), b) ' + (h2 | true)) ≠ (mem ⊕ (h1 + (h2 | true)))(l := v) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: restrict-W: ⊦ h |W = h.filter(λ vpe. vpe._1.W?); restrict-loc: ⊦ h | l = h.filter(λ vpe. vpe._1.l = l); restrict-vp: ⊦ h | b = h.filter(λ vpe. vpe._2 ↔ b); a: ⊦ (x + y) + z = x + y + z; from specification list

Proof step 3 from proof lastwrite-to-update (previous step) (back to tree)

h2.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h2.filter(._2)) ≠ (mem ⊕ (h1 + h2.filter(._2)))(l := v) ⊦

User applied rule induction

And obtained the following new goals

Rule argument

indvar: # h2 wfpred: <

Additional information

Used simplifier rules: <; (wellfounded) Used terms: # h2

Proof step 4 from proof lastwrite-to-update (previous step) (back to tree)

h2.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h2.filter(._2)) ≠ (mem ⊕ (h1 + h2.filter(._2)))(l := v), ∀ h, l, mem, h1, t, v, b. # h < # h2 → h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) ≠ (mem ⊕ (h1 + h.filter(._2)))(l := v) → false ⊦

User applied rule cut formula

And obtained the following new goals

Rule argument

fma: h2 = []

Additional information

Used simplifier rules: overwrite-attach-write: ⊦ mem ⊕ (h + (W(t, l, v), b) ') = (mem ⊕ h)(l := v); ⊦ [].filter(p) = []; (s) ⊦ x + [] = x; (s) a: ⊦ (x + y) + z = x + y + z; from specification list Used formulas: h2 = []

Proof step 5 from proof lastwrite-to-update (previous step) (back to tree)

h2.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], h2 ≠ [], mem ⊕ (h1 + (W(t, l, v), b) ' + h2.filter(._2)) ≠ (mem ⊕ (h1 + h2.filter(._2)))(l := v), ∀ h, l, mem, h1, t, v, b. # h < # h2 → h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) ≠ (mem ⊕ (h1 + h.filter(._2)))(l := v) → false ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: list, name:lastdiv-rew, seq: ⊦ x = [] ↔ ¬(∃ y, a. x = y + a '), subst:[x] → [h2]; ['a] → [(RWevent, Bool)], <all paths>

Additional information

Used terms: h2

Proof step 6 from proof lastwrite-to-update (previous step) (back to tree)

⊦ x = [] ↔ ¬(∃ y, a. x = y + a ')

A spec-lemma

Proof step 7 from proof lastwrite-to-update (previous step) (back to tree)

h2.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h2.filter(._2)) ≠ (mem ⊕ (h1 + h2.filter(._2)))(l := v), ∃ y, a. h2 = y + a ', ∀ h, l, mem, h1, t, v, b. # h < # h2 → h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) ≠ (mem ⊕ (h1 + h.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ a '.filter(p) = (p(a) ⊃ a ';[]); (s) ⊦ (x + y).filter(p) = x.filter(p) + y.filter(p); (s) ⊦ x + y = [] ↔ x = [] ∧ y = []; (s)

Proof step 8 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], (vpe._1.W? ⊃ vpe ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (vpe._2 ⊃ vpe ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (vpe._2 ⊃ vpe ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + vpe ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic elimination applied rule apply elim lemma

And obtained the following new goals

Rule argument

term: vpe._1

Additional information

Used terms: e, b0

Proof step 9 from proof lastwrite-to-update (previous step) (back to tree)

(e.W? ⊃ vpe ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], vpe = (e, b0), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ vpe ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ vpe ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + vpe ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: a: ⊦ (x + y) + z = x + y + z; from specification list

Proof step 10 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], (e.W? ⊃ (e, b0) ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (e, true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (e, true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (e, b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule apply induction

And obtained the following new goals

Rule argument

subst: [h0, l, mem, h1, t, v, b] → [h, l, mem, h1, t, v, b]

Additional information

Used simplifier rules: ⊦ #(x + y) = # x + # y; (s) ⊦ # a ' = 0 +1; (s) a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ ¬ n < n; (s) a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic c: ⊦ m + n = n + m; from specification nat-basic Used terms: h, l, mem, h1, t, v, b

Proof step 11 from proof lastwrite-to-update (previous step) (back to tree)

(e.W? ⊃ (e, b0) ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (e, true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (e, true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (e, b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦ h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) ≠ (mem ⊕ (h1 + h.filter(._2)))(l := v)

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 12 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], (e.W? ⊃ (e, b0) ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (e, true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (e, true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (e, b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule constructor cut

And obtained the following new goals

Rule argument

var: e

Additional information

Used simplifier rules: RWevent freely generated by R, W;;

Proof step 13 from proof lastwrite-to-update (previous step) (back to tree)

(e.W? ⊃ (e, b0) ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], e = R(t0, l0, v0), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (e, true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (e, true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (e, b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ [].filter(p) = []; (s) ⊦ ¬ R(t, l, v).W?; (s)

Proof step 14 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (R(t0, l0, v0), true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (R(t0, l0, v0), true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (R(t0, l0, v0), b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule case distinction

And closed the goal!

Rule argument

pos: left 3

Additional information

Used simplifier rules: overwrite-attach-read: ⊦ mem ⊕ (h + (R(t, l, v), b) ') = mem ⊕ h; ⊦ x + [] = x; (s) a: ⊦ (x + y) + z = x + y + z; from specification list

Proof step 15 from proof lastwrite-to-update (previous step) (back to tree)

(e.W? ⊃ (e, b0) ';[]).filter(λ vpe. vpe._1.l = l).filter(._2) = [], h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], e = W(t0, l0, v0), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (e, true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (e, true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (e, b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ W(t, l, v).l = l; (s) ⊦ a '.filter(p) = (p(a) ⊃ a ';[]); (s) ⊦ W(t, l, v).W?; (s)

Proof step 16 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], (l0 = l ⊃ (W(t0, l, v0), b0) ';[]).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (b0 ⊃ (W(t0, l0, v0), true) ';[])) ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (W(t0, l0, v0), true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 4

Additional information

Used simplifier rules: ⊦ x + [] = x; (s) a: ⊦ (x + y) + z = x + y + z; from specification list

Proof step 17 from proof lastwrite-to-update (previous step) (back to tree)

(l0 = l ⊃ (W(t0, l, v0), b0) ';[]).filter(._2) = [], h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], b0, mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2) + (W(t0, l0, v0), true) ') ≠ (mem ⊕ (h1 + h.filter(._2) + (b0 ⊃ (W(t0, l0, v0), true) ';[])))(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), b0) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: overwrite-attach-write: ⊦ mem ⊕ (h + (W(t, l, v), b) ') = (mem ⊕ h)(l := v); a: ⊦ (x + y) + z = x + y + z; from specification list

Proof step 18 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], (l0 = l ⊃ (W(t0, l, v0), true) ';[]).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), (mem ⊕ (h1 + h.filter(._2)))(l := v)(l0 := v0) ≠ (mem ⊕ (h1 + h.filter(._2)))(l0 := v0)(l := v), ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), true) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 2

Additional information

Used simplifier rules: ⊦ a '.filter(p) = (p(a) ⊃ a ';[]); (s) ⊦ a ' ≠ []; (s)

Proof step 19 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], [].filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), (mem ⊕ (h1 + h.filter(._2)))(l := v)(l0 := v0) ≠ (mem ⊕ (h1 + h.filter(._2)))(l0 := v0)(l := v), l0 ≠ l, ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), true) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ [].filter(p) = []; (s)

Proof step 20 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), (mem ⊕ (h1 + h.filter(._2)))(l := v)(l0 := v0) ≠ (mem ⊕ (h1 + h.filter(._2)))(l0 := v0)(l := v), l0 ≠ l, ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), true) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule expand left

And obtained the following new goals

Rule argument

pos: left 3

Additional information

Proof step 21 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), (mem ⊕ (h1 + h.filter(._2)))(l := v)(l0 := v0)(l1) ≠ (mem ⊕ (h1 + h.filter(._2)))(l0 := v0)(l := v)(l1), l0 ≠ l, ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), true) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 22 from proof lastwrite-to-update (previous step) (back to tree)

h.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [], mem ⊕ (h1 + (W(t, l, v), b) ' + h.filter(._2)) = (mem ⊕ (h1 + h.filter(._2)))(l := v), (l0 = l1 ⊃ v0;(l = l1 ⊃ v;((mem ⊕ (h1 + h.filter(._2))))(l1))) ≠ (l = l1 ⊃ v;(l0 = l1 ⊃ v0;((mem ⊕ (h1 + h.filter(._2))))(l1))), l0 ≠ l, ∀ h0, l, mem, h1, t, v, b. # h0 < #(h + (W(t0, l0, v0), true) ') → h0.filter(λ vpe. vpe._1.W?).filter(λ vpe. vpe._1.l = l).filter(._2) = [] ∧ mem ⊕ (h1 + (W(t, l, v), b) ' + h0.filter(._2)) ≠ (mem ⊕ (h1 + h0.filter(._2)))(l := v) → false ⊦

User applied rule case distinction

And closed the goal!

Rule argument

pos: left 3

Additional information

Proof Tree for lastwrite-to-update (View conclusion)

The following image shows the proof tree of sequent calculus. The proved goal is at the bottom. You can click on the nodes to view additional rules. See here for details on colors in a proof tree.

the proof tree