> Meer, Hans van der <mailto:H.vanderMeer@uva.nl>
> 11. April 2016 um 10:35
> I seem to remember the following variations in \startuseMPgraphic.
>
> (1) \startuseMPgraphic{name}{comma separated list of variables}
> (2) \startuseMPgraphic{name}{comma separated list of key=value pairs}
> In the second case one is able to set a default value to that 
> variable, possibly to be overridden with \useMPgraphic{name}{key=value}.
> I very much would like to specify default values on the 
> \startuseMPgraphic definition of the graphic.
>
> However, I cannot get option (2) working. Do I have a bad memory 
> (possible of course ;-), Has it to be done otherwise?
> In the example below the graphic myname1 is ok, but myname2 gives the 
> following error:
> metapost > error:
> >> orange
> ! Improper type.
> <to be read again>
>                    ;
> <*> ...raw unitsquare scaled 1cm withcolor orange;
>
> minimal example:
>
> \starttext
> \startuseMPgraphic{myname1}{color}
>   pickup pencircle scaled 1mm;
>   draw unitsquare scaled 1cm withcolor \MPvar{color};
> \stopuseMPgraphic
>
> \startuseMPgraphic{myname2}{color=red}
>   pickup pencircle scaled 1mm;
>   draw unitsquare scaled 1cm withcolor \MPvar{color};
> \stopuseMPgraphic
>
> \useMPgraphic{myname1}{color=blue}
> \useMPgraphic{myname2}{color=orange}
>
> \stoptext
\startuseMPgraphic{hans}{color}
   pickup pencircle scaled 1mm;
   draw unitsquare scaled 1cm withcolor \MPvar{color};
\stopuseMPgraphic

\setupMPvariables[hans][color=red]

\starttext

\useMPgraphic{hans}

\useMPgraphic{hans}{color=blue}

\stoptext

Wolfgang