On Sun, 30 Jul 2017, Henning Hraban Ramm wrote:

> Am 2017-07-29 um 00:57 schrieb Aditya Mahajan <adityam@umich.edu>:
>
>> On Fri, 28 Jul 2017, Henning Hraban Ramm wrote:
>> 
>>> Ahoi again,
>>> 
>>> I’m preparing some ConTeXt docs with a lot of examples and would like to reproduce what we have in the wiki as
>>> 
>>> <context source="yes">
>>> ...
>>> </context>
>>> 
>>> i.e. sourcecode beside the result.
>>> 
>>> Often the shown source is exactly what I want to show, in other cases I need some additional setup that I don’t want to show.
>>> 
>>> Which approach would you suggest? Combinations?
>> 
>> \startbuffer[example-1]
>> ....
>> \stopbuffer
>> 
>> 
>> \placesidebyside
>>    {\typebuffer[example-1]}
>>    {\getbuffer[setups, example-1]}
>
>
> Thank you again, that should be enough for most of my small examples.
> I guess I never heard of or forgot about \placesidebyside as well as \placeontopofeachother.
>
> But I’d like to show a lot of similar examples to explain several options.
> Therefore, if I’d like to simplify my code, but this doesn’t work:
>
> \def\CodeExample#1{%
> \startbuffer[zB]
> #1
> \stopbuffer
> \typebuffer[zB]
> \getbuffer[zB]
> }
>
> \CodeExample{\framed[frame=off,leftframe=on,rulethickness=1em,framecolor=blue]{Klotz am Bein}}

You can't do that with buffers. If you need to define your own macros that 
behave like buffers, you need to use \grabbufferdata (see buff-ini.mkiv). 
But in this case, there is a simpler solution:

\defineframed
   [CodeExampleFramed]
   [
     frame=off,
     width=0.5\textwidth,
     align=normal,
   ]

\definebuffer
     [CodeExample]

\define\stopCodeExample
     {\placesidebyside
 	{\CodeExampleFramed{\typeCodeExample}}
 	{\CodeExampleFramed{\getCodeExample}}}


\starttext
\startCodeExample
\framed
   [
     frame=off,
     leftframe=on,
     rulethickness=1em,
     framecolor=blue,
   ]{Klotz am Bein}
\stopCodeExample


\stoptext