throat alike

[jimmywarting]

Think it would be useful if you could implement some like throat so you could specify how many parallel yields is possible

consider this example

co(function* (){
    const book = fetch("books/mobidick")
    const chapters = book.chapters
    let pages = []

    // use 5 paralle http request at the same time
    yield co(5, function* {
        for(chapter of chapters){
            let page = yield fetch("books/mobidick/chapters/" + chapter.index)
            pages[chapter.index] = page
        }
    })

    return pages
})

[epoberezkin]

That's not possible, really. The idea is that the value that yield returns is resolved and the code continues to execute synchronously.

For parallel requests you need to yield an array (or object) with promises, so your example can be this:

co(function* (){
    const book = fetch("books/mobidick")
    const chapters = book.chapters
    let pages = []

    chapters.forEach((chapter) => {
        pages[chapter.index] = fetch("books/mobidick/chapters/" + chapter.index);
    });
    return yield pages;
});