| ⊦ 1 < # sks → (rk ∈ st[r -- sks, val] ↔ rk ∈ st ∨ rk = st[r -- sks .butlast] .refval -- sks .last) |
⊦ rk ∈ st[r -- sks, val] ↔ rk ∈ st ∨ rk = st[r -- sks .butlast] .refval -- sks .last, # sks = 1, sks = []
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ # sks = 0 ↔ sks = []], [CSIMPSEQ : ⊦ 1 < m ↔ ¬ (m = 0 ∨ m = 1)])]]