File-handle streams (was: Redirecting messages)

[John Wiegley]

>>>>> Daniel Colascione <address@hidden> writes:

> I wish we'd direct some love toward the streams system. There's no reason
> that standard-output and a hypothetical message-output couldn't be the same
> type of object and have the same semantics. A scheme like this would also
> help modes like ielm provide a uniform way of capturing command output.

I want this too, Daniel. I'd also like to have a way of making streams from
file handles directly, so Eshell could finally support input redirection.
Something like:

    (with-file-stream "/tmp/foo" :mode 'write :var handle
       (prin1 some-object handle))

At the moment it's rather hard to generate huge amounts of data to a file
quickly, since you have to use a buffer in between. Eshell's piping behavior
would also be orders of magnitude faster, since it now uses a temporary buffer
to accumulate and then send data from one process to another.

Anyone interested in tackling this challenge?

John