delete all whitespace (space) in a region

delete all whitespace (space) in a region

[Uwe Brauer]

Hi

I have constructs like
$\left[ \left( \partial_{t}\Phi  \right)^{2} -                 \left\vert \nabla\Phi \right\vert^{2}   \right]^{\frac{1+K}{2K}}$:

That contain to much ........

So I am looking for a region-wise command deleting all this .. With the result
$\left[\left(\partial_{t}\Phi\right)^{2}-\left\vert \nabla\Phi\right\vert^{2}\right]^{\frac{1+K}{2K}}$:

(defun my-delete-all-whitespace-region (beg end)
  (interactive "r")
  (query-replace " " "" nil beg end nil nil))

Seems to be a very simple solution, but maybe too simple?

Any comments?

Uwe Brauer 

--
I strongly condemn Hamas heinous atrocities on Israel, especially the despicable pogroms.
I strongly condemn Putin's war of aggression against Ukraine.
I support to deliver weapons to Ukraine's military.
I support the NATO membership of Ukraine.
I support the EU membership of Ukraine.
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

Re: delete all whitespace (space) in a region

[Manuel Giraud via Users list for the GNU Emacs text editor]

Uwe Brauer <oub@mat.ucm.es> writes:

> Hi
>
> I have constructs like
> $\left[ \left( \partial_{t}\Phi  \right)^{2} -                 \left\vert \nabla\Phi \right\vert^{2}   \right]^{\frac{1+K}{2K}}$:
>
> That contain to much ........
>
> So I am looking for a region-wise command deleting all this .. With the result
> $\left[\left(\partial_{t}\Phi\right)^{2}-\left\vert \nabla\Phi\right\vert^{2}\right]^{\frac{1+K}{2K}}$:
>
> (defun my-delete-all-whitespace-region (beg end)
>   (interactive "r")
>   (query-replace " " "" nil beg end nil nil))
>
> Seems to be a very simple solution, but maybe too simple?

If you don't want to confirm for the replacements, you could instead do
this:

--8<---------------cut here---------------start------------->8---
(defun my-delete-all-whitespace-region (beg end)
  (interactive "r")
  (save-excursion
    (goto-char beg)
    (while (re-search-forward " " end t)
      (replace-match ""))))
--8<---------------cut here---------------end--------------->8---
-- 
Manuel Giraud

Re: delete all whitespace (space) in a region

[tpeplt]

Manuel Giraud via Users list for the GNU Emacs text editor
<help-gnu-emacs@gnu.org> writes:
>
> If you don't want to confirm for the replacements, you could instead do
> this:
>
> (defun my-delete-all-whitespace-region (beg end)
>   (interactive "r")
>   (save-excursion
>     (goto-char beg)
>     (while (re-search-forward " " end t)
>       (replace-match ""))))

Emacs 28 added the function ‘replace-string-in-region’.

(defun my-delete-all-whitespace-region (beg end)
  (interactive "r")
  (save-excursion
    (replace-string-in-region " " "" beg end)))

--

Re: delete all whitespace (space) in a region

[Emanuel Berg]

tpeplt wrote:

> Emacs 28 added the function ‘replace-string-in-region’.
>
> (defun my-delete-all-whitespace-region (beg end)
>   (interactive "r")
>   (save-excursion
>     (replace-string-in-region " " "" beg end)))

(defun delete-all-whitespace (&optional beg end)
  (interactive
    (when (use-region-p)
      (list (region-beginning) (region-end)) ))
  (or beg (setq beg (point-min)))
  (or end (setq end (point-max)))
  (save-mark-and-excursion
    (replace-string-in-region " " "" beg end) ))

A pretty fancy interface to a one-liner function with
hardcoded data :)

-- 
underground experts united
https://dataswamp.org/~incal

Re: delete all whitespace (space) in a region

[tomas]

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On Wed, Nov 08, 2023 at 09:24:53PM -0500, tpeplt wrote:
> Manuel Giraud via Users list for the GNU Emacs text editor
> <help-gnu-emacs@gnu.org> writes:
> >
> > If you don't want to confirm for the replacements, you could instead do
> > this:
> >
> > (defun my-delete-all-whitespace-region (beg end)
> >   (interactive "r")
> >   (save-excursion
> >     (goto-char beg)
> >     (while (re-search-forward " " end t)
> >       (replace-match ""))))

A small optimisation would be to use the regexp " +", meaning one
or more spaces.

> 
> Emacs 28 added the function ‘replace-string-in-region’.
> 
> (defun my-delete-all-whitespace-region (beg end)
>   (interactive "r")
>   (save-excursion
>     (replace-string-in-region " " "" beg end)))

To have this here, you'd have to "replace-regexp-in-region", of
course.

Cheers
-- 
t

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Re: delete all whitespace (space) in a region

[Uwe Brauer]

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>>> "t" == tpeplt  <tpeplt@gmail.com> writes:

> Manuel Giraud via Users list for the GNU Emacs text editor
> <help-gnu-emacs@gnu.org> writes:
>> 
>> If you don't want to confirm for the replacements, you could instead do
>> this:
>> 
>> (defun my-delete-all-whitespace-region (beg end)
>> (interactive "r")
>> (save-excursion
>> (goto-char beg)
>> (while (re-search-forward " " end t)
>> (replace-match ""))))

> Emacs 28 added the function ‘replace-string-in-region’.

> (defun my-delete-all-whitespace-region (beg end)
>   (interactive "r")
>   (save-excursion
>     (replace-string-in-region " " "" beg end)))

Ah, thanks, I did not know that

-- 
I strongly condemn Hamas heinous atrocities on Israel, especially the despicable pogroms.
I strongly condemn Putin's war of aggression against Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the NATO membership of Ukraine.
I support the EU membership of Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

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Re: delete all whitespace (space) in a region

[tpeplt]

Uwe Brauer <oub@mat.ucm.es> writes:

>
>> Emacs 28 added the function ‘replace-string-in-region’.
>
>> (defun my-delete-all-whitespace-region (beg end)
>>   (interactive "r")
>>   (save-excursion
>>     (replace-string-in-region " " "" beg end)))
>
> Ah, thanks, I did not know that

If you want to see more of what has been added, see the NEWS file by
typing C-h n.  Unfortunately, this file (for Emacs 28) is large (4000
lines) and the new function above is not mentioned until line 3540.

A new feature that was added Emacs 28 is the ‘shortdoc-display-group’.
Type:
   M-x shortdoc-display-group <TAB>
to see a list of the groups for which shortdoc help is available.  These
are only a subset of the functions that are available in Emacs.

Type:
   M-x shortdoc-display-group <RET>

and then type "buffer" (no quotes) in response to the prompt:

   Show summary for functions in: buffer

This will then list brief help/descriptions for many buffer-related
functions in a ‘shortdoc’ buffer, including ‘replace-string-in-region’.

--

Re: delete all whitespace (space) in a region

[Uwe Brauer]

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>>> "EB" == Emanuel Berg <incal@dataswamp.org> writes:

> tpeplt wrote:
>> Emacs 28 added the function ‘replace-string-in-region’.
>> 
>> (defun my-delete-all-whitespace-region (beg end)
>> (interactive "r")
>> (save-excursion
>> (replace-string-in-region " " "" beg end)))

> (defun delete-all-whitespace (&optional beg end)
>   (interactive
>     (when (use-region-p)
>       (list (region-beginning) (region-end)) ))
>   (or beg (setq beg (point-min)))
>   (or end (setq end (point-max)))
>   (save-mark-and-excursion
>     (replace-string-in-region " " "" beg end) ))

> A pretty fancy interface to a one-liner function with
> hardcoded data :)

Right, but well I would only use this function region wide never on the
whole buffer. That is why I prefer *(interactive "r")*

-- 
I strongly condemn Hamas heinous atrocities on Israel, especially the despicable pogroms.
I strongly condemn Putin's war of aggression against Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the EU and NATO membership of Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

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Re: delete all whitespace (space) in a region

[Andreas Röhler]

Am 09.11.23 um 06:34 schrieb tomas@tuxteam.de:
> On Wed, Nov 08, 2023 at 09:24:53PM -0500, tpeplt wrote:
>> Manuel Giraud via Users list for the GNU Emacs text editor
>> <help-gnu-emacs@gnu.org>  writes:
>>> If you don't want to confirm for the replacements, you could instead do
>>> this:
>>>
>>> (defun my-delete-all-whitespace-region (beg end)
>>>    (interactive "r")
>>>    (save-excursion
>>>      (goto-char beg)
>>>      (while (re-search-forward " " end t)
>>>        (replace-match ""))))
> A small optimisation would be to use the regexp " +", meaning one
> or more spaces.
>
>> Emacs 28 added the function ‘replace-string-in-region’.
>>
>> (defun my-delete-all-whitespace-region (beg end)
>>    (interactive "r")
>>    (save-excursion
>>      (replace-string-in-region " " "" beg end)))
> To have this here, you'd have to "replace-regexp-in-region", of
> course.
>
> Cheers

BTW the code using replace-string-in-region and the form above are not 
equivalent.

The latter updates the end, whereas the previous keeps the old limit, 
which may do unexpected deletions.

Cheers,

Andreas

Re: delete all whitespace (space) in a region

[Michael Heerdegen]

Andreas Röhler <andreas.roehler@easy-emacs.de> writes:

> The latter updates the end, whereas the previous keeps the old limit,
> which may do unexpected deletions.

Indeed.  In such cases using markers is useful:

  (unless (markerp end)
    (setq end (copy-marker end)))

If you want to be kind to the gc, invalidate the marker at the end of
the function:

  (move-marker end nil)


Michael.