Delay a computation in another thread

[Chris Angelico]

On Sat, Sep 2, 2017 at 8:53 PM, Steve D'Aprano
<steve+python at pearwood.info> wrote:
> The problem is that after the message is printed, the REPL's prompt is
> disrupted. This is especially annoying when I'm in the middle of typing a line.
> This is just a cosmetic flaw, but it would be nice if I could tell Python to
> redraw the current line. For example, using _ to indicate the position of the
> cursor, this is what happens now:
>
> py> class K:
> ...     attribute =It is Sat Sep  2 20:48:39 2017 and 2+2 is 4
> _
>
>
> This is what I'd prefer:
>
> py> class K:
> ...     attribute =It is Sat Sep  2 20:48:39 2017 and 2+2 is 4
> ...     attribute =_
>

This is a common problem with a lot of programs. I'd like a solution
too; the place I'd go looking would be readline, as that's where most
of the work is going to be happening. (Also, if it's added as a
readline feature, it won't break redirection or anything like that, as
it's specifically a human-interaction thing.)

There are three parts to the console output: the prompt ("..."), your
input ("attribute ="), and the output message. Only readline knows
exactly which parts go where.

ChrisA