bug#73431: Add `setf` support for `stream.el` in ELPA

[Michael Heerdegen via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Michael Heerdegen via "Bug reports for GNU Emacs, the Swiss army knife
of text editors" <bug-gnu-emacs@gnu.org> writes:

> How much slower or faster is forcing with this change, in the end?

I now tried el-search using your patch.  Everything worked well and so
far I did not see any obvious performance degradation.

> > +      (bad-output
> > +       (error "Bad output from stream updater: %s"
> > +              bad-output)))
>                                                   ^^
>
> Should this better be %S (we use %s for strings only)?

Also: when compiling using master I get

| stream.el:395:15: Warning: docstring wider than 80 characters
| stream.el:421:15: Warning: docstring has wrong usage of unescaped single
|     quotes (use \=' or different quoting such as `...')

Could you please try to care about these?

But apart from these details your patches look fine to me.  Thanks for
working on this.


Michael.