| ⊦ key1 < key0, ∀ key. (key ∈ ri |≤ key0 |≤ key1 ↔ key ∈ ri |≤ key0) ∧ (key ∈ ri |≤ key0 |≤ key1 → (ri |≤ key0 |≤ key1)[key] = (ri |≤ key0)[key]) |
⊦ key1 < key0, (key ∈ ri ∧ ¬ key0 < key → ¬ key1 < key) ∧ (key ∈ ri ∧ ¬ key0 < key ∧ ¬ key1 < key → (ri |≤ key0 |≤ key1)[key] = ri[key])
Used simplifier rules: in-le: ⊦ key0 ∈ ri |≤ key1 ↔ key0 ∈ ri ∧ ¬ key1 < key0;%at-le: ⊦ ¬ key1 < key0 ∧ key0 ∈ ri → (ri |≤ key1)[key0] = ri[key0];