Fix and clarify async-ready, async-get and async-wait (#71).

[thierryvolpiatto]

• async.el (async-ready): Ensure proc buffer is alive
  and return t if buffer is not alive. Fix docstring.
  (async--wait): Renamed from async-wait.
  (async-get): Ensure proc buffer is alive. Fix docstring.
  (async-start): Docstring only.

[thierryvolpiatto]

@jwiegley Please verify I am not wrong in the return value of async-ready and also about making async-wait private.

Thanks.

[jwiegley]

async-wait is intended to be a user-facing function that returns when async-get would not block. Why did you want to make it private?

[thierryvolpiatto]

John Wiegley <notifications@github.com> writes:

async-wait is intended to be a user-facing function that returns when async-get would not block.

Ok, can you give some examples, perhaps in test file ?

Why did you want to make it private?

I had the impression it was only used internally, but was unsure about its usage, why I asked ;-). Thanks.

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-- Thierry

[jwiegley]

The example is simply this: If you call async-get, it will block until the future provides a value, and then return that value. If you call async-wait, it will also block until the future provides a value, but it does not return that value -- it leaves it unclaimed in the future. It provides a way to say, "I want to wait until the future is ready", without doing anything with that value.

[thierryvolpiatto]

John Wiegley <notifications@github.com> writes:

The example is simply this: If you call async-get, it will block until the future provides a value, and then return that value. If you call async-wait, it will also block until the future provides a value, but it does not return that value -- it leaves it unclaimed in the future. It provides a way to say, "I want to wait until the future is ready", without doing anything with that value.

Thanks for explanation. However I think there is a bug here which makes an infloop in `async-wait` if user touch a key, you can reproduce with following code: (let ((proc (async-start (lambda () (sit-for 3) (message "hello") )))) (async-wait proc)) If you eval this code and touch nothing, it returns nil, ok, but if you hit a key before it finishes, it hangup forever. A solution is using `sleep-for` in `async-wait` instead of `sit-for`. WDYT?

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-- Thierry

[jwiegley]

Sure, that sounds good to me.

[thierryvolpiatto]

John Wiegley <notifications@github.com> writes:

Merged #72.

Thanks, rebased and merged in ELPA.

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-- Thierry