>#WIP
hseval (Add x y) = x + y
hslet (a, b, c) = (1, 2, 3)
mldatatype stone = Black | White
datatype cell = Empty | Full of stone
fun isSequence s = case s of
(Full Black, Full Black, Full Black) => true
| (Full White, Full White, Full White) => true
| other => false
case
の糖衣構文