Globbing file name match function?

Globbing file name match function?

[Lars Ingebrigtsen]

I've been poking around for a couple of minutes to see whether we have a
function to list files matching a regexp a la how a shell matches them.
That is:

$ ls ~/src/emacs/*/lisp/abbrev.el
/home/larsi/src/emacs/27.1/lisp/abbrev.el
/home/larsi/src/emacs/bisect/lisp/abbrev.el
/home/larsi/src/emacs/emacs-28/lisp/abbrev.el
/home/larsi/src/emacs/foo/lisp/abbrev.el
...

This is with a glob, but ideally you'd be able to drop in a regexp
anywhere in the file name.  Do we have that anywhere in Emacs?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Re: Globbing file name match function?

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Sun, 05 Jun 2022 13:11:04 +0200
> 
> I've been poking around for a couple of minutes to see whether we have a
> function to list files matching a regexp a la how a shell matches them.
> That is:
> 
> $ ls ~/src/emacs/*/lisp/abbrev.el
> /home/larsi/src/emacs/27.1/lisp/abbrev.el
> /home/larsi/src/emacs/bisect/lisp/abbrev.el
> /home/larsi/src/emacs/emacs-28/lisp/abbrev.el
> /home/larsi/src/emacs/foo/lisp/abbrev.el
> ...
> 
> This is with a glob, but ideally you'd be able to drop in a regexp
> anywhere in the file name.  Do we have that anywhere in Emacs?

ls-lisp.el does.  It converts a wildcard to regexp, and then uses
directory-files with MATCH set to the regexp.

Do you mean specifically a wildcard in the middle of a file name,
which stands for matching subdirectories?

Re: Globbing file name match function?

[Lars Ingebrigtsen]

Eli Zaretskii <eliz@gnu.org> writes:

> Do you mean specifically a wildcard in the middle of a file name,
> which stands for matching subdirectories?

Yes.  The leaf part matching is covered by directory-files well enough.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Re: Globbing file name match function?

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: emacs-devel@gnu.org
> Date: Sun, 05 Jun 2022 13:25:33 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Do you mean specifically a wildcard in the middle of a file name,
> > which stands for matching subdirectories?
> 
> Yes.  The leaf part matching is covered by directory-files well enough.

But what glob does is recursively find each wildcard, expand it, then
go deeper and repeat.  So it should be possible to do the same based
on directory-files, I think?

Re: Globbing file name match function?

[Lars Ingebrigtsen]

Eli Zaretskii <eliz@gnu.org> writes:

> But what glob does is recursively find each wildcard, expand it, then
> go deeper and repeat.  So it should be possible to do the same based
> on directory-files, I think?

Yes, and I wondered if we had that already.

Andreas Schwab <schwab@linux-m68k.org> writes:

> There is file-expand-wildcards.

Ah, thanks, just what I was looking for.  (Not under the name I was
looking for, though.)  Hm...  it takes globs, but it looks trivial to
expand to regexps.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Re: Globbing file name match function?

[Stefan Monnier]

>> There is file-expand-wildcards.
> Ah, thanks, just what I was looking for.  (Not under the name I was
> looking for, though.)

FWIW it recently took me a while to find it as well (I first looked for
something with "glob" in its name).  Luckily I knew we had such
a function (and I remembered it's used by `find-file`).


        Stefan

Re: Globbing file name match function?

[Philip Kaludercic]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>> But what glob does is recursively find each wildcard, expand it, then
>> go deeper and repeat.  So it should be possible to do the same based
>> on directory-files, I think?
>
> Yes, and I wondered if we had that already.
>
> Andreas Schwab <schwab@linux-m68k.org> writes:
>
>> There is file-expand-wildcards.
>
> Ah, thanks, just what I was looking for.  (Not under the name I was
> looking for, though.)  Hm...  it takes globs, but it looks trivial to
> expand to regexps.

Should an alias be added with "glob" in the name, something like
"glob-expand" or just "glob", like the libc function?

Re: Globbing file name match function?

[Lars Ingebrigtsen]

Philip Kaludercic <philipk@posteo.net> writes:

> Should an alias be added with "glob" in the name, something like
> "glob-expand" or just "glob", like the libc function?

If we're bikeshedding, I think both "expand" and "wildcard" are
misleading here.  😀  I think of "$HOME" -> "/home/larsi" as an
expansion.  What this function does is search for files that match a
pattern.

So `file-find-<something>' would be natural, but we call visiting a file
`find-file', so that's confusing, too.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Re: Globbing file name match function?

[Andreas Schwab]

On Jun 05 2022, Lars Ingebrigtsen wrote:

> If we're bikeshedding, I think both "expand" and "wildcard" are
> misleading here.

The standard term is filename expansion.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

Re: Globbing file name match function?

[Andreas Schwab]

On Jun 05 2022, Lars Ingebrigtsen wrote:

> I've been poking around for a couple of minutes to see whether we have a
> function to list files matching a regexp a la how a shell matches them.
> That is:
>
> $ ls ~/src/emacs/*/lisp/abbrev.el
> /home/larsi/src/emacs/27.1/lisp/abbrev.el
> /home/larsi/src/emacs/bisect/lisp/abbrev.el
> /home/larsi/src/emacs/emacs-28/lisp/abbrev.el
> /home/larsi/src/emacs/foo/lisp/abbrev.el
> ...
>
> This is with a glob, but ideally you'd be able to drop in a regexp
> anywhere in the file name.  Do we have that anywhere in Emacs?

There is file-expand-wildcards.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."