Side navigation
#9016 closed enhancement (wontfix)
Opened April 29, 2011 01:08PM UTC
Closed April 29, 2011 01:55PM UTC
.then() should return a new promise
| Reported by: | sifu@0xx0.net | Owned by: | |
|---|---|---|---|
| Priority: | undecided | Milestone: | 1.next |
| Component: | deferred | Version: | 1.5.2 |
| Keywords: | Cc: | ||
| Blocked by: | Blocking: |
Description
other promise implementations return a new promise from .then(). that way, you can pass values down the chain.
eg see: https://github.com/sifu/jquery-deferred/blob/master/jquery.deferred.js#L241
Attachments (0)
Change History (2)
Changed April 29, 2011 01:40PM UTC by comment:1
| component: | unfiled → deferred |
|---|---|
| type: | bug → enhancement |
Changed April 29, 2011 01:55PM UTC by comment:2
| resolution: | → wontfix |
|---|---|
| status: | new → closed |
Yes, pipe is what you need.
I know we broke the Promises/A contract not implementing this behaviour on then() but the general use case is to bind callbacks and having then() create a new Deferred everytime under the hood was a bit heavy-weight to say the least. We preferred to make it explicit: if you wanna chain, use pipe() (as in shell pipe -- get original Deferred output in, return a value or a new Observable out).
I talked with Kris Zyp about this and he seemed quite happy with the way jQuery implemented Promises and was not at all bothered by this deviation.
I believe we have accomplished this functionality in jQuery 1.6 with Deferred.pipe(), which has already landed.