Than you Hans!  
My plan is simply to use the output of a sagemath run in this way. A run should produce 
several files containing TeX code. I only wanted to shorten the \startbuffer \input ... \stopbuffer
sequence. Maybe this (including sagemath output) could be done differently, but this was 
the first (and only ;-)) idea I came up with.

kind regards
Erik

On Wed, Mar 30, 2016 at 10:11 AM, Hans Hagen <pragma@wxs.nl> wrote:
On 3/30/2016 9:27 AM, Erik Margraf wrote:
Dear List,

please help me with my problem here ....

I - probably naively - tried the following:
------------------------

\starttext


\def\Buffer#1#2

{

\startbuffer[#1]

\input #2

\stopbuffer

}

\Buffer{bla}{knuth}


\stoptext

-------------------------


Context gives me the following error on this:


tex error > tex error on line 9 in file
C:/Users/emargraf/Documents/buffer.tex: ! Undefined control sequence



\Buffer ...startbuffer [#1] \input #2 \stopbuffer

l.9 \Buffer{bla}{knuth}

\startbuffer .. \stopbuffer is parsed special

so use:

\def\Buffer#1#2
  {\setbuffer[#1]{\input #2\relax}}

\Buffer{bla}{knuth}

but i'm not sure what you gain here as it will still input tufte each time

Hans

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