| ⊦ ⌜x⌝ to 1 = ⌜a '⌝ ↔ ⌜x⌝ [0] = a, ⌜x⌝ = [] |
⊦ x = [], x to 1 = a ' ↔ x.first = a
Used simplifier rules: to-fin: ⊦ ⌜x⌝ to n = ⌜x to n⌝ ;%sel-fin: ⊦ ⌜x⌝ [n] = x[n];%fin-empty: ⊦ ⌜x⌝ = [] ↔ x = [];%get-zero: ⊦ x ≠ [] → x[0] = x.first; from specification list-del%inj-02: ⊦ ⌜x⌝ = ⌜x0⌝ ↔ x = x0; from specification stream-basic