How to add comments in a plain list

How to add comments in a plain list

[René]

Is there a way to insert comments in a plain list without breaking it into two
distinct lists?

Such a list:

 1. first
 2. second
 # comment about second item
 3. third
 4. fourth

is actually considered as

 1. first
 2. second
 # comment about second item
 1. third
 2. fourth

Re: How to add comments in a plain list

[Bernt Hansen]

René <jlr_0@yahoo.com> writes:

> Is there a way to insert comments in a plain list without breaking it into two
> distinct lists?
>
> Such a list:
>
>  1. first
>  2. second
>  # comment about second item
>  3. third
>  4. fourth
>
> is actually considered as
>
>  1. first
>  2. second
>  # comment about second item
>  1. third
>  2. fourth

You can ident the comment like this

 1. first
 2. second

    # comment about second item

 3. third
 4. fourth

-Bernt

Re: Re: How to add comments in a plain list

[Eric S Fraga]

At Tue, 22 Sep 2009 00:16:14 -0400, Bernt Hansen wrote:
> René <jlr_0@yahoo.com> writes:
> > Is there a way to insert comments in a plain list without breaking it into two
> > distinct lists?

I've run into exactly this problem in the past few days, preparing a
document, intended for export to a variety of formats, containing a
number of enumerated lists.

> You can ident the comment like this
> 
>  1. first
>  2. second
> 
>     # comment about second item
> 
>  3. third
>  4. fourth
> 
> -Bernt

I had already tried this but the export breaks.  At least for me,
indented comments come out in ascii, latex and html exports.  Is there
an option that turns off that behaviour?  I haven't seen one...

Thanks,
eric

Re: How to add comments in a plain list

[René]

Bernt Hansen <bernt <at> norang.ca> writes:
> You can ident the comment like this
> 
>  1. first
>  2. second
> 
>     # comment about second item
> 
>  3. third
>  4. fourth

Unfortunately in this case your comment gets exported since the `#' is indented.

Of course one doesn't want the comments to appear in the html version of the
document. 

Is there a way to easily solve this issue?

Re: Re: How to add comments in a plain list

[Carsten Dominik]

On Sep 22, 2009, at 12:32 PM, René wrote:

> Bernt Hansen <bernt <at> norang.ca> writes:
>> You can ident the comment like this
>>
>> 1. first
>> 2. second
>>
>>    # comment about second item
>>
>> 3. third
>> 4. fourth
>
> Unfortunately in this case your comment gets exported since the `#'  
> is indented.
>
> Of course one doesn't want the comments to appear in the html  
> version of the
> document.
>
> Is there a way to easily solve this issue?

You can always add a function to one of the org-export-preprocess-...  
hooks.
However, if you are not careful, you might remove something like

    #!/bin/sh

    in a source code block, or some normal text where,
    #25 starts a new line by accident.

It may be relatively safe to look for # followed by space, or
lines that have only "#" ad the only nonwhite character on a line.

Something like this might work (untested)

(add-hook
  'org-export-preprocess-before-backend-specifics-hook
  (lambda ()
    (goto-char (point-min))
    (while (re-search-forward "^[ \t]+#\\([ \t]*$\\| .*$\\)\n?" nil t)
      (org-if-unprotected-at (match-beginning 1)
       (replace-match "")))))


HTH

- Carsten

Re: Re: How to add comments in a plain list

[Bernt Hansen]

Eric S Fraga <ucecesf@ucl.ac.uk> writes:

> At Tue, 22 Sep 2009 00:16:14 -0400, Bernt Hansen wrote:
>> René <jlr_0@yahoo.com> writes:
>> > Is there a way to insert comments in a plain list without breaking it into two
>> > distinct lists?
>
> I've run into exactly this problem in the past few days, preparing a
> document, intended for export to a variety of formats, containing a
> number of enumerated lists.
>
>> You can ident the comment like this
>> 
>>  1. first
>>  2. second
>> 
>>     # comment about second item
>> 
>>  3. third
>>  4. fourth
>> 
>> -Bernt
>
> I had already tried this but the export breaks.  At least for me,
> indented comments come out in ascii, latex and html exports.  Is there
> an option that turns off that behaviour?  I haven't seen one...

If you're actually trying to make the comment not export this seems to
work for me

 1. first
 2. second
 #+ comment about second item
 3. third
 4. fourth

-Bernt

Re: Re: How to add comments in a plain list

[Eric S Fraga]

At Tue, 22 Sep 2009 08:52:13 -0400, Bernt Hansen wrote:
> If you're actually trying to make the comment not export this seems to
> work for me
> 
>  1. first
>  2. second
>  #+ comment about second item
>  3. third
>  4. fourth
> 
> -Bernt

and in fact it works without the + sign and that's what I was using
initial, as was the OP (René I guess).  however, we're going around in
circles here because comments at column 0 cause org-mode to consider
the next item to start a new list so your fourth item (if you hit C-c
C-c on it) will be renumbered to 1, as indicated by the OP!

Basically, we wish to have comments which don't interrupt the list
numbering *and* are not exported either.  Is this possible?

thanks,
eric

Re: Re: How to add comments in a plain list

[Bernt Hansen]

Eric S Fraga <ucecesf@ucl.ac.uk> writes:

> At Tue, 22 Sep 2009 08:52:13 -0400, Bernt Hansen wrote:
>> If you're actually trying to make the comment not export this seems to
>> work for me
>> 
>>  1. first
>>  2. second
>>  #+ comment about second item
>>  3. third
>>  4. fourth
>> 
>> -Bernt
>
> and in fact it works without the + sign and that's what I was using
> initial, as was the OP (René I guess).  however, we're going around in
> circles here because comments at column 0 cause org-mode to consider
> the next item to start a new list so your fourth item (if you hit C-c
> C-c on it) will be renumbered to 1, as indicated by the OP!
>
> Basically, we wish to have comments which don't interrupt the list
> numbering *and* are not exported either.  Is this possible?

At column 0 - probably not.

 1. first
 2. second
    #+ comment about second item
    #+ Another comment goes here
 3. third
 4. fourth

The #+ comment probably isn't officially supported either... it just
happens to work.  Sorry about the run-around :)

-Bernt

Re: Re: How to add comments in a plain list

[Eric S Fraga]

At Tue, 22 Sep 2009 10:10:41 -0400,
Bernt Hansen wrote:
> At column 0 - probably not.
> 
>  1. first
>  2. second
>     #+ comment about second item
>     #+ Another comment goes here
>  3. third
>  4. fourth
> 
> The #+ comment probably isn't officially supported either... it just
> happens to work.  Sorry about the run-around :)
> 
> -Bernt

Ah ha!  Of the four combinations (# versus #+ and column 0 or not),
this one works perfectly!  Thanks.

Re: How to add comments in a plain list

[René]

Eric S Fraga <ucecesf <at> ucl.ac.uk> writes:
> At Tue, 22 Sep 2009 10:10:41 -0400, Bernt Hansen wrote:
> > At column 0 - probably not.
> > 
> >  1. first
> >  2. second
> >     #+ comment about second item
> >     #+ Another comment goes here
> >  3. third
> >  4. fourth
> > 
> > The #+ comment probably isn't officially supported either... it just
> > happens to work.  Sorry about the run-around :)

Unfortunately, in this case Emacs doesn't fontify those lines as if they were
comments.

Re: Re: How to add comments in a plain list

[Carsten Dominik]

On Sep 22, 2009, at 7:30 PM, René wrote:

> Eric S Fraga <ucecesf <at> ucl.ac.uk> writes:
>> At Tue, 22 Sep 2009 10:10:41 -0400, Bernt Hansen wrote:
>>> At column 0 - probably not.
>>>
>>> 1. first
>>> 2. second
>>>    #+ comment about second item
>>>    #+ Another comment goes here
>>> 3. third
>>> 4. fourth
>>>
>>> The #+ comment probably isn't officially supported either... it just
>>> happens to work.  Sorry about the run-around :)
>
> Unfortunately, in this case Emacs doesn't fontify those lines as if  
> they were
> comments.

It does now.

- Carsten

Re: Re: How to add comments in a plain list

[Eric S Fraga]

At Thu, 24 Sep 2009 10:27:57 +0100, Carsten Dominik wrote:
> On Sep 22, 2009, at 7:30 PM, René wrote:
> > Unfortunately, in this case Emacs doesn't fontify those lines as if
> > they were comments.
> 
> It does now.
> 
> - Carsten

Carsten, thanks for this.  It works perfectly.

But this leads to me a more general question for all of you emacs
experts: comments in my org files typically consist of /less
important/ text and so I like to de-emphasise the text by changing the
face used (to a light gray, in my case, compared with the default of
firebrick).  However, for programming, I prefer the default.  Can
somebody suggest how I can have a different font-lock-comment-face for
org-mode files without making a global change?  Should I put something
in the org-mode hook?

Or even on a per-file basis?  I've tried using Emacs local variables
but haven't found the right incantation... :(

Any suggestions more than welcome!

Thanks,
eric

Re: Re: How to add comments in a plain list

[Carsten Dominik]

On Sep 25, 2009, at 11:10 AM, Eric S Fraga wrote:

> At Thu, 24 Sep 2009 10:27:57 +0100, Carsten Dominik wrote:
>> On Sep 22, 2009, at 7:30 PM, René wrote:
>>> Unfortunately, in this case Emacs doesn't fontify those lines as if
>>> they were comments.
>>
>> It does now.
>>
>> - Carsten
>
> Carsten, thanks for this.  It works perfectly.
>
> But this leads to me a more general question for all of you emacs
> experts: comments in my org files typically consist of /less
> important/ text and so I like to de-emphasise the text by changing the
> face used (to a light gray, in my case, compared with the default of
> firebrick).  However, for programming, I prefer the default.  Can
> somebody suggest how I can have a different font-lock-comment-face for
> org-mode files without making a global change?  Should I put something
> in the org-mode hook?
>
> Or even on a per-file basis?  I've tried using Emacs local variables
> but haven't found the right incantation... :(
>
> Any suggestions more than welcome!

Hi Eric,

I don't know how to change `font-lock-comment-face' on a per-buffer  
level.

What you can do though (I think) is use the function `font-lock-add- 
keywords'
to add your own regular expression for matching comments and specify
an arbitrary font for this match.  For example (untested):

  (font-lock-add-keywords 'org-mode
   '(("^[ \t]*#.*" 0 my-org-comment-face prepend)))

- Carsten