Re: Matching labels with buttons

[Heime <heimeborgia@protonmail.com>]

On Tuesday, July 16th, 2024 at 9:50 AM, Stephen Berman <stephen.berman@gmx.net> wrote:

> On Mon, 15 Jul 2024 21:29:38 +0000 Heime heimeborgia@protonmail.com wrote:
> 
> > On Tuesday, July 16th, 2024 at 9:20 AM, Stephen Berman
> > stephen.berman@gmx.net wrote:
> > 
> > > On Mon, 15 Jul 2024 17:25:42 +0000 Heime heimeborgia@protonmail.com wrote:
> > > 
> > > > On Tuesday, July 16th, 2024 at 4:24 AM, Heime heimeborgia@protonmail.com wrote:
> 
> [...]
> 
> > > > > I also have to handle the case of " LABEL [-] " with a different regex,
> > > > > so I can
> > > > > distinguish between " [-] LABEL " and " LABEL [-] ".
> > > > 
> > > > In the latter case I want to match [-] at the end with any trailing spaces.
> > > 
> > > With your original code amended by anchoring the first regexp as I
> > > suggested, I think it handles both cases you want; at least the brief
> > > tests I tried worked. If you don't get the results you want, please
> > > show the complete code you're using and examples where it fails.
> > > 
> > > Steve Berman
> > 
> > Have used
> > 
> > "\\`\\(\\s-\\[\\-\\]\\s-\\)\\(.*\\)" for " [-] LABEL "
> > 
> > and
> > 
> > "\\(.\\)\\(\\s-\\[\\-\\]\\s-*\\)\\'" for " LABEL [-] "
> 
> 
> Since you didn't do what I requested, I've done it. Evaluate the
> following code, which is based on your original code amended as I
> suggested (I didn't use "\\'" in the second regexp, but the results are
> the same with and without it):

Was that about showing the code ?  It is basically writing down the regex strings.

> (defun heime-button (label)
> (if (string-match "\\`\\(\\s-\\[\\-\\]\\s-\\)\\(.\\)" label) ; [-] LB
> (progn
> (setq bt (match-string 1 label))
> (setq lb (match-string 2 label))
> (setq result
> (concat bt (propertize lb 'face '(:foreground "red")))))
> (when (string-match "\\(.\\)\\(\\s-\\[\\-\\]\\s-\\)" label) ; LB [-]
> (setq lb (match-string 1 label))
> (setq bt (match-string 2 label))
> (setq result
> (concat (propertize lb 'face '(:foreground "red")) bt))))
> (insert result))
> 
> (with-current-buffer (get-buffer-create "Heime Test")
> (erase-buffer)
> (heime-button " [-] LABEL ")
> (newline)
> (heime-button " LABEL [-] "))
> 
> (switch-to-buffer "Heime Test")
> 
> What I see in buffer Heime Test is this:
> 
> [-] LABEL
> LABEL [-]
> 
> where each string "LABEL" is red. Is this not what you want?
> 
> Steve Berman

Yes it is what I wanted.  Having read the documentation, why don't you apply 
\\' for the second case to match the empty string, but only at the end of string
being matched against ?