Re: noweb-start and noweb-end header args

[Amy Grinn <grinn.amy@gmail.com>]

Amy Grinn <grinn.amy@gmail.com> writes:

> Ihor Radchenko <yantar92@posteo.net> writes:
>
>> Amy Grinn <grinn.amy@gmail.com> writes:
>>
>>> I would like to add support for setting 'org-babel-noweb-wrap-start and
>>> 'org-babel-noweb-wrap-end for each src block individually
>>
>> May you please explain the use case when changing the default values
>> is useful?
>
> Of course!  Changing the default values can be useful to prevent syntax
> highlighting errors in a specific language.  In the example I gave, <<<
> and >>> aren't recognized as the beginning of a heredoc in a shell
> script the way <<firewall-safe-mode>> would be.

To expand on this, some major modes can fundamentally conflict with the
default noweb syntax.  Here is a valid shell script *and* a valid noweb
reference to a block named EOF:

cat <<EOF>> file.txt
Hello
EOF

I hope this helps explain why the wrap-start and wrap-end options were
necessary to include more than a decade ago.  In terms of actually using
them, it's a bit cumbersome, especially in Org mode buffers that use
multiple languages.

The second diff I sent (under the termux handle, accidentally) is my
preferred solution (:noweb yes <<< >>>).  This would avoid the need for
new header arguments to be introduced while maintaining backwards
compatibility.  It also feels natural to specify the two options
together: I can't think of a good reason to only need to specify the
wrap-end option.