Jonas Sicking (2015-02-27T23:07:56.000Z)
On Thu, Feb 26, 2015 at 11:43 PM, Andrea Giammarchi
<andrea.giammarchi at gmail.com> wrote:
> AFAIK bluebird did:
> https://github.com/petkaantonov/bluebird/blob/master/API.md#cancelerror-reason---promise
>
> But I agree once you've made Promises more complex than events ( xhr in this
> case ) nobody wins :-/
>
> Although, specially for fetch or anything network related, there **must** be
> a way to bloody cancel that!
>
> ....right?

Yeah. Most IO operations do need a way to cancel. And hopefully all of
them will be returning Promises.

I definitely agree that providing cancelability on Promise will add
complexity. That said, the pattern of making heavy long-running APIs
return a Promise, and wanting to enable cancelling them, is likely
going to be common.

So finding a good solution to that pattern seems worthwhile.

/ Jonas
d at domenic.me (2015-03-06T01:10:32.516Z)
On Thu, Feb 26, 2015 at 11:43 PM, Andrea Giammarchi <andrea.giammarchi at gmail.com> wrote:
> AFAIK bluebird did:
> https://github.com/petkaantonov/bluebird/blob/master/API.md#cancelerror-reason---promise
>
> But I agree once you've made Promises more complex than events ( xhr in this
> case ) nobody wins :-/
>
> Although, specially for fetch or anything network related, there **must** be
> a way to bloody cancel that!
>
> ....right?

Yeah. Most IO operations do need a way to cancel. And hopefully all of
them will be returning Promises.

I definitely agree that providing cancelability on Promise will add
complexity. That said, the pattern of making heavy long-running APIs
return a Promise, and wanting to enable cancelling them, is likely
going to be common.

So finding a good solution to that pattern seems worthwhile.