gh-147950: Additionally bind yank-arg to M-_ in pyrepl

[L3viathan]

(I think this is a trivial change, but if I'm mistaken I'm of course happy to create an issue for this after all.)

This change just additionally binds M-_ (or Meta-Underscore, or Escape-Underscore) to yank-arg; inserting the last word of the previous line. In GNU Readline there's two bindings for this, M-. and M-_ (and my muscle memory is unfortunately used to the latter).

• Issue: _pyrepl: Additionally bind yank-arg to M-_ #147950

[picnixz]

Let's have an issue (or re-use an old one if you can find one related to such changes) and add a NEWS entry as well. It's still a user-visible change somehow though minimal and could be considered a bugfix.

[picnixz]

I think this change is fine but for posterity can you post the link motivating this change (that is, the link to the GNU docs that does this or give an HTML page that docs please?)

[L3viathan]

It's mentioned in the docs for bash.

[picnixz]

Please avoid updating the branch if the CI is ok. We just need to wait for a REPL maintainer to accept that change (cc @ambv, @pablogsal)

[chris-eibl]

I've just talked to @ambv at the EuroPython 2026 sprints and this LGTU.

Thanks @L3viathan for your contribution!

[L3viathan]

@chris-eibl Thanks, that's a nice goodbye present from Kraków for me :)

(on a plane back home)