define-minor-mode: what's the purpose of the BODY argument?

define-minor-mode: what's the purpose of the BODY argument?

[Raffaele Ricciardi]

Hello there,

the documentation of `define-minor-mode' begins with:

— Macro: define-minor-mode mode doc [init-value [lighter [keymap]]]
keyword-args... body...

Then it continues with documenting what the purpose of each argument is, 
but it
fails to do so for the BODY argument.  So, what's the purpose of that 
argument?
Is it code to be run every time the mode is activated or deactivated, 
and such
code can check `prefix-argument' to determine whether it should activate or
deactivate itself?

Thanks.

RE: define-minor-mode: what's the purpose of the BODY argument?

[Drew Adams]

> the documentation of `define-minor-mode' begins with:
> 
> Macro: define-minor-mode mode doc [init-value [lighter [keymap]]]
> keyword-args... body...
> 
> Then it continues with documenting what the purpose of each 
> argument is, but it fails to do so for the BODY argument.  So,
> what's the purpose of that argument?  Is it...?

You should not have to guess.

To find out the answer, file a doc bug report. ;-)
Each of the arguments should be described in the doc string.

M-x report-emacs-bug

Re: define-minor-mode: what's the purpose of the BODY argument?

[Raffaele Ricciardi]

On 08/16/2012 03:05 PM, Drew Adams wrote:
 >> the documentation of `define-minor-mode' begins with:
 >>
 >> Macro: define-minor-mode mode doc [init-value [lighter [keymap]]]
 >> keyword-args... body...
 >>
 >> Then it continues with documenting what the purpose of each
 >> argument is, but it fails to do so for the BODY argument.  So,
 >> what's the purpose of that argument?  Is it...?
 >
 > You should not have to guess.
 >
 > To find out the answer, file a doc bug report. ;-)
 > Each of the arguments should be described in the doc string.
 >
 > M-x report-emacs-bug
 >
 >

Well, I discovered that the argument is indeed documented, only not as
prominently as the others.  Therefore I missed it, also because arguments in
Info mode are not highlighted the way I'm used to in Help mode.  I 
apologize for
the inconvenience.

Re: define-minor-mode: what's the purpose of the BODY argument?

[Raffaele Ricciardi]

On 08/16/2012 06:23 PM, Raffaele Ricciardi wrote:
 > Well, I discovered that the argument is indeed documented, only not as
 > prominently as the others.  Therefore I missed it, also because
 > arguments in
 > Info mode are not highlighted the way I'm used to in Help mode.  I
 > apologize for
 > the inconvenience.

And to avoid cutting a sorry figure like this one in the future, I've 
written a
snippet of code to highlight arguments in Info mode, too, and I'm 
attaching it.
Arguments are empirically identified as symbols of two or more uppercase
letters, digits or dashes, starting with a letter.

I would have preferred using the `help-argument-name' face, but on my
installation this face misbehaves (I've filed a bug report), so I'm using
`font-lock-comment-face'.


(defun rr-Info-mode-highlight-argument-names ()
   "Highlight argument names as they are highlighted in Help mode."
   ;; To avoid highlighting uppercase single letters in the text, highlight
   ;; only symbols more than one character long.
   (font-lock-add-keywords nil
                           '(("\\_<[A-Z][-A-Z[:digit:]]+\\_>"
                              . font-lock-comment-face))))

(add-hook 'Info-mode-hook #'rr-Info-mode-highlight-argument-names)

RE: define-minor-mode: what's the purpose of the BODY argument?

[Drew Adams]

FYI - Info+ fontifies entries for reference items (functions, macros, commands,
special forms, constants, options, other variables), and that includes their
parameters, even those on continuation lines.

http://www.emacswiki.org/emacs/InfoPlus

> I've written a snippet of code to highlight arguments in Info
> mode, too, and I'm attaching it.  Arguments are empirically
> identified as symbols of two or more uppercase
> letters, digits or dashes, starting with a letter.
> 
> (defun rr-Info-mode-highlight-argument-names ()
>    "Highlight argument names as they are highlighted in Help mode."
>    (font-lock-add-keywords nil
>                            '(("\\_<[A-Z][-A-Z[:digit:]]+\\_>"
>                               . font-lock-comment-face))))
> (add-hook 'Info-mode-hook #'rr-Info-mode-highlight-argument-names)