Kokaの例: Generator

code:koka(js)

effect yield<a>

fun yield(x: a): ()

fun traverse(xs: list<a>): yield<a> ()

match xs

Cons(x,xx) -> { yield(x); traverse(xx) }

Nil -> ()

handle部分

code:koka(js)

fun main(): console ()

with fun yield(i: int)

println("yielded " ++ i.show)

code:result

yielded 1

yielded 2

yielded 3

yielded 4

yielded 5

参考

恐らく古いverionのKokaで書かれてる

the concepts (especially effects & effect handlers) allows making your own generators, async-await, and stuff like that all