drain(�) is a coroutine

drain(�) is a coroutine

[GvR, 2014-02-26 00:01:08]

Let me think about this. There was something clever about this. I think it was
allowing code that would keep writing (without ever yielding) until the buffer
is full, e.g.

while True:
    while True:
        s.write(b'x')
        w = s.drain()
        if w:
            break
    yield from w

But this may be excessively clever.

[haypo_gmail, 2014-02-26 00:11:37]

On 2014/02/26 00:01:08, GvR wrote:
> Let me think about this. There was something clever about this. I think it was
> allowing code that would keep writing (without ever yielding) until the buffer
> is full, e.g.
> 
> while True:
>     while True:
>         s.write(b'x')
>         w = s.drain()
>         if w:
>             break
>     yield from w
> 
> But this may be excessively clever.

It makes the common case look weird. If you consider this use case important
enough, why not adding a method to check if the buffer is full which would
simply return a boolean?

I never had to check if a write buffer is full or not.

[GvR, 2014-02-26 00:18:04]

What's weird about the common case? You can just write

s.write(b'x')
yield from s.drain()

There's normally no need to check for drain()'s return value.