cc and await in Promise are very similar, but call/cc does not stop the process and Promise cannot be re-executed await only connects the current continuation after the given Promise, but does not expose the continuation to the user It seems possible to mimic the behavior of await with call/cc, but not vice versa. JavaScript Scheme There was this article.
- [Implement Maybe, Either, Promise, Continuation Monad and do syntax in JavaScript + generator and compare with async-await - Qiita https://qiita.com/legokichi/items/0582e71f4e 6984548933]
- Relationship between async, generator, Promise, CPS, and monad in ES2017 - Qiita
ts
let p = new Promise((resolve) => {
console.log("promise called", resolve);
// @ts-ignore
window.resolve = resolve;
});
(async () => {
console.log("before await")
console.log(await p);
console.log("after await")
})()
// display before await and abort processing
window.resolve(42)
// 42
// after await // Suspended processing is resumed
// undefined
window.resolve(53)
// undefined // nothing happens after the second timescheme
(define resolve #f)
(define (p c)
(print "promise called")
(print c)
(set! resolve c))
gosh> (begin
(print "before call/cc")
(print (call/cc p))
(print "after call/cc"))
;before call/cc
;promise called
;#<subr "continuation">
;#<subr "continuation">
;after call/cc
;#<undef>
Processing is executed to the end.
gosh> resolve
#<subr "continuation">
gosh> (resolve 42)
42
after call/cc
#<undef>
; Runs again.
gosh> (resolve 53)
53
after call/cc
#<undef>
; Runs as many times as you want.
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