Re: Comments and control lines (# vs. #+)

[Mark Shoulson <mark@kli.org>]

Samuel Wales <samologist <at> gmail.com> writes:

> 
> The following, which is general and I wrote a long time ago,
> might also be relevant to the recent thread on comments
> breaking lists.
> 
> ===
> 
> There might be really good reasons for the #+ comment
> convention in Org, but I am not sure what they are.  So
> please bear with me.

Probably the most important one is that # is often used in ordinary writing
without the intent of commenting out the rest of the line.  Like saying "We're 
#1" or talking about #hashtags.  It could be escaped for things like that, 
maybe, but the whole point is to keep the markup as minimal and unobtrusive as
possible.  Comments are specifically a departure from the norm; they are things
*excluded* from the usual functioning of whatever they're in.  Let _them_ be
what has to get extra markup.  #+ is a sufficiently rare combination that it
can be spared.

> This list is not complete or minimal.  Please disregard the
> items you don't like.

Most of them can't really counter the above issue, I think (you may feel
otherwise).

>   1) #+ is not as standard as #

Standards are per-format anyway.

>   2) there are tools for commenting and uncommenting regions
>      with #, but not with #+

Org is its own tool.  If it needs region-commenting features, let them be
added, and they can use #+.  Besides, the COMMENT keyword in headlines
also comments out regions quite effectively (if the region is a subtree).

>   4) imported (or pasted) text will often have # commenting
>      and this will need special processing to make it work
>      with Org

This is perfectly sensible if you're a programmer (I haven't seen # used as
a comment character anywhere outside of computer-parsable input).  Org has a
much larger scope than talking about programming.  I would say that "Imported
(or pasted) text will often have # without intending to comment and this will
need special processing..."  That's more or less what I said above.

Org is mainly about prose.  If you're pasting in programs with comments they
probably belong in code-blocks anyway.

>   5) fill functions and packages often don't understand #+

Org is its own tool, and is what's best suited for editing org files.

>   6) plain # works in column 0 in Org, leading to user
>      expectation that it will behave consistently in other
>      columns as it does in most other languages that use #

# in column 0 is a special case precisely for something simpler than #+ since
# is rarely seen in column 0 in ordinary text, though it could happen if a
# sign or something like #1 happened to be wrapped at a bad place.
This present paragraph does serve as a counterexample, to be sure, but
I think it is a rare case.

~mark