bug#37538: [PATCH] Add docstring for `tags-complete-tags-table-file'.

[Eli Zaretskii]

> From: Hong Xu <hong@topbug.net>
> Cc: larsi@gnus.org,  37538@debbugs.gnu.org
> Date: Sat, 12 Oct 2019 11:46:25 -0700
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> > How about the below:
> >
> >   (defun tags-complete-tags-table-file (string predicate what)
> >     "Complete STRING from file names in the current tags table.
> >   PREDICATE, if non-nil is a function to filter possible matches:
> >   if it returns nil, the match is ignored.  If PREDICATE is nil,
> >   every possible match is acceptable.
> >   WHAT is a flag specifying the type of completion: t means 
> > `all-completions'
> >   operation, any other value means `try-completions' operation.
> >
> >   This function serves as COLLECTION argument to `completing-read',
> >   see the Info node `(elisp) Programmed Completion' for more detailed
> >   description of the arguments."
> 
> Looks good to me. Thanks.

Thanks, I installed it.