Irrelevant src blocks can break noweb expansion

Irrelevant src blocks can break noweb expansion

[Berry, Charles]

I used to avoid this by `(setq org-babel-use-quick-and-dirty-noweb-expansion t)'.

This illustrates the issue:

#+begin_src org

  ,* abc

  ,#+begin_src R :comment (message "running on empty")

  ,#+end_src

  ,#+begin_src R :noweb yes
  1
  ,#+end_src


#+end_src

The irrelevant, unnamed, empty src block its consulted via org-babel-get-src-block-info.  This runs the (message ...) expression.  Not much of a problem here, but I sometimes have a src block in my buffer that is a work-in-progress and has a header arg that calls a function I would not ordinarily have loaded.  When noweb does its thing, it chokes on the lack of a function.

Chuck

Re: Irrelevant src blocks can break noweb expansion

[Nicolas Goaziou]

Hello,

"Berry, Charles" <ccberry@ucsd.edu> writes:

> I used to avoid this by `(setq org-babel-use-quick-and-dirty-noweb-expansion t)'.
>
> This illustrates the issue:
>
> #+begin_src org
>
>   ,* abc
>
>   ,#+begin_src R :comment (message "running on empty")
>
>   ,#+end_src
>
>   ,#+begin_src R :noweb yes
>   1
>   ,#+end_src
>
>
> #+end_src
>
> The irrelevant, unnamed, empty src block its consulted via
> org-babel-get-src-block-info.

When? AFAICT, the second block doesn't contain any Noweb reference, so
there is nothing to consult in the first place. IOW, something is
missing in your recipe.

Also, `org-babel-use-quick-and-dirty-noweb-expansion' was intended to
skip properties check when collecting Noweb references from the buffer.
I.e., Org would only trust "name" keyword and ":noweb-ref" header
argument. Since there is no property in your example, I fail to see why
`org-babel-use-quick-and-dirty-noweb-expansion' would apply here.

Regards,

-- 
Nicolas Goaziou

Re: Irrelevant src blocks can break noweb expansion

[Berry, Charles]

> On Dec 11, 2017, at 11:42 PM, Nicolas Goaziou <mail@nicolasgoaziou.fr> wrote:
> 
>> 
>> The irrelevant, unnamed, empty src block its consulted via
>> org-babel-get-src-block-info.
> 
> When? AFAICT, the second block doesn't contain any Noweb reference, so
> there is nothing to consult in the first place. IOW, something is
> missing in your recipe.

You are right. 

I had a problem with a subtree export seeming to fail at an unused src block and thought I had tracked it down to a bad header arg. But my example was clearly not right. And in trying the failed export again it worked. So I am deeply baffled.  If this problem shows up again, I'll do a better job of tracking it down.

Thanks,

Chuck