Hi list,

I realized that circleit throws an error.
It works fine if I replace boxes_generic_declare by boxes_declare in line 244 in mp-xbox.mpxl

rboxit is probably affected as well, but I did not test that.

MWE:
\startMPinclusions
input boxes;
\stopMPinclusions

\startMPpage
circleit.a(textext("$X$"));
drawboxed(a);
\startMPpage

The error (truncated) message:
metapost        > initializing instance 'metafun:1' using format 'metafun' and method 'default'
metapost        > loading 'metafun' as 'metafun.mpxl' using method 'default'
metapost        > initializing number mode 'scaled'
metapost        > trace > This is MPLIB for LuaMetaTeX, version 3.11, running in scaled mode.
metapost        > trace >
metapost        > trace > loading metafun for lmtx, including the plain 1.004 base definitions
metapost        > trace >
metafun         > log >
metafun         > log > error: Isolated expression
metafun         > log >
metapost        > trace > <error> boxes_generic_declare
metapost        > trace > <to be read again> (
metapost        > trace > <macro> circleit -> (TEXT3)-> begingroup.boxes_begin("boxes_the_circle","boxes_size_circle",(SUFFIX2),(TEXT3));boxes_generic_declare(pair)_n.n,_n.s,_n.e,_n.w;(SUFFIX2)e-(SUFFIX2)c=(SUFFIX2)c-(SUFFIX2)w=((SUFFIX2)dx,0)+0.5*(lrcorner.boxes_pic(SUFFIX2)-llcorner.boxes_pic(SUFFIX2));(SUFFIX2)n-(SUFFIX2)c=(SUFFIX2)c-(SUFFIX2)s=(0,(SUFFIX2)dy)+0.5*(ulcorner.boxes_pic(SUFFIX2)-llcorner.boxes_pic(SUFFIX2));boxes_end(boxes_clear_circle,(SUFFIX2));endgroup
metafun         > log >
metafun         > log > I couldn't find an '=' or ':=' after the expression that is shown above this
error message, so I guess I'll just ignore it and carry on.
metafun         > log >
metapost        > trace > <direct> circleit.a(textext("$X$")); drawboxed(a); ;
metapost        > trace >

Cheers,
Jacob