Alternative to Promise

Forbes Lindesay forbes at
Thu Oct 1 09:20:35 UTC 2015

You seem to be picking on q as the standard promise implementation, but it's actually one of the most complex implementation of a promise and does far more than just implement the standard.

If you want to see how a simpler implementation (which just implements promises/A+) would look, I suggest you read 

> On 1 Oct 2015, at 02:40, 韩冬 <handong05 at> wrote:
> Yeah, it seemed i do have a hard time to figure out how the state transition worked from the source code. I always can’t manage state transition in js clearly, especially under async operations.
>> On Oct 1, 2015, at 8:49 AM, Tab Atkins Jr. <jackalmage at> wrote:
>> On Wed, Sep 30, 2015 at 5:46 PM, 韩冬 <handong05 at> wrote:
>>> Now take a look at even a very simple Promise library Q form its design document:
>>>> The "state machine" isn't complex.  "unresolved" goes to either
>>>> "resolved to another promise", "fulfilled", or "rejected".  "resolved
>>>> to another promise" eventually turns into "fulfilled" or "rejected".
>>>> Or, of course, hangs, which "unresolved" can also do.
>>> With all these state transition added, it’s quiet complex to me to figure out how does it work, i have to go back and read the design process from 1 to 7.
>>> Should we expect future js programmers just use it, or understand it before use it?
>> If you think what I said above, in your quote, is complex, then I
>> really can't help you.
>> ~TJ
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