Am 09.10.2011 22:01, schrieb Meer, H. van der:

I have this question on the implementation of metapost. The following program ends in an error:

\startMPpage picture v; draw origin--(1cm,1cm); v = currentpicture; clearit; draw (1cm,0)--(0,1cm); currentpicture := currentpicture + v;

use addto currentpicture also v;

\stopMPpage

The error is: ! Not implemented: (picture)+(picture). Yet Knuth's metafont book in Chapter 13 tells me, quote: "Pictures can be added or subtracted;" Is the current metafont implementation lacking this feature? Will it be implemented in the near future?

Just another notation, that's all. Best wishes, Peter