Re: [BABEL] BUG Re: Omitting try/catch blocks from tangled R code?

[Eric Schulte <schulte.eric@gmail.com>]

John Hendy <jw.hendy@gmail.com> writes:

> On Fri, Feb 7, 2014 at 1:22 PM, Rainer M Krug <Rainer@krugs.de> wrote:
>>
>>
>>
>> On 02/07/14, 17:47 , Eric Schulte wrote:
>> > Rainer M Krug <Rainer@krugs.de> writes:
>> >
>> >> On 02/07/14, 07:18 , John Hendy wrote:
>> >>> Greetings,
>> >>>
>> >>>
>> >>> I don't usually tangle, but am creating a code file to go along with a
>> >>> presentation I'm giving this weekend so that attendees can try things
>> >>> out afterward by cloning my github repo where all the data and
>> >>> necessary files are stored.
>> >>>
>> >>> In my presentation (Beamer), I create plots via the R pdf() device,
>> >>> and noticed that all of the tangled code where plots are generated
>> >>> contains the following:
>> >>>
>> >>> pdf(file="file.pdf"); tryCatch({
>> >>>
>> >>>   code block contents here
>> >>>
>> >>> },error=function(e){plot(x=-1:1, y=-1:1, type='n', xlab='', ylab='',
>> >>> axes=FALSE); text(x=0, y=0, labels=e$message, col='red');
>> >>> paste('ERROR', e$message, sep=' : ')}); dev.off()
>> >>>
>> >>> Is there a way to omit this?
>> >>
>> >> This is a bug which must have been introduced some time ago - in the
>> >> stock version of emacs (Org-mode version 7.9.3f
>> >> (release_7.9.3f-17-g7524ef @
>> >> /usr/local/Cellar/emacs/24.3/share/emacs/24.3/lisp/org/)) it does not
>> >> tangle the enclosing commands to create graphics, but in 8.2 it does (I
>> >> don't have an older version at hand to go further back).
>> >>
>> >
>> > I believe this was introduced by your commit eaa3a761d.  Reversion of
>> > which with the following should provide a temporary workaround.
>>

I take this back, the behavior is unrelated to Rainer's commit adding
try/catch blocks to R graphics creation logic.

In fact I don't believe this is a bug, rather the default behavior is to
expand code block bodies on tangling.  This behavior may be changed by
using the :no-expand header argument which will inhibit code block body
expansion during tangling.

Best,

-- 
Eric Schulte
https://cs.unm.edu/~eschulte
PGP: 0x614CA05D