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Re: Optional Arguments
From: |
pietru |
Subject: |
Re: Optional Arguments |
Date: |
Mon, 7 Dec 2020 19:13:06 +0100 |
I'm having a go at returning the two values from a function
(defun word-markers ()
(let ((ma mb))
(skip-chars-backward "[:alpha:]")
(setq ma (point))
(skip-chars-forward "[:alpha:]")
(setq mb (point))
(cons ma mb) ))
(defun test ()
(interactive)
(let ((deactivate-mark nil) bounds $ma $mb)
(if (use-region-p)
(setq $ma (region-beginning) $mb (region-end))
(save-excursion
(setq bounds (word-markers))
(setq $mu (car bounds))
(setq $mv (car bounds)) ))
(message "Bounds: %s" $bounds)
(message "Region: [%s, %s]" $ma $mb) ))
But something's not right.
> Sent: Monday, December 07, 2020 at 4:38 PM
> From: tomas@tuxteam.de
> To: pietru@caramail.com
> Cc: "Help Gnu Emacs" <help-gnu-emacs@gnu.org>
> Subject: Re: Optional Arguments
>
> On Mon, Dec 07, 2020 at 03:24:36PM +0100, pietru@caramail.com wrote:
>
> [...]
>
> > > => "ma: 15 mb: 26"
> >
> > Hmmm. Variables local to function.
>
> Yes. "Local" meaning here either dynamical extent (called functions
> "see" the variables up the call chain, think Unix shells) or
> lexical extent (code contexts "see" the variables of enclosing
> code contexts (think C or Java or...), depending on whether you
> chose lexical binding [1].
>
> [...]
>
> > > ...would you expect it to change the number 15 to whatever the word's
> > > beginning position is? You would mess up maths with that :)
> >
> > Yes, it would mess up.
>
> Gödel's nothing against that :-D
>
> Cheers
>
> [1] Cf. Chapter "Lexical Binding" in the Elisp manual, or here
>
> https://www.gnu.org/software/emacs/manual/html_node/elisp/Lexical-Binding.html
>
> - t
>
- Optional Arguments, pietru, 2020/12/06
- Re: Optional Arguments, Alexis Roda, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, tomas, 2020/12/07
- Re: Optional Arguments, Anders Dalskov, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, tomas, 2020/12/07
- Re: Optional Arguments,
pietru <=
- Re: Optional Arguments, Arthur Miller, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, Michael Heerdegen, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, Arthur Miller, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, Alexis Roda, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07
- Re: Optional Arguments, tomas, 2020/12/07
- Re: Optional Arguments, pietru, 2020/12/07