Something goes wrong with this simple example: <--- snip ---> \definemathoverarrow [overrightarrow] [\rightarrowfill] \def\Ray#1{\overrightarrow{#1}} \starttext Hello world! $\Ray{ABC}$. \stoptext <--- snip ---> It leads to: ! Missing $ inserted. <inserted text> $ <to be read again> \displaystyle \dodohandlemathoverarrow ...{\ialign {##\crcr #2#3 \crcr \noalign {\kern #1\n... \mathpalette ...>\mathchoice {#1\displaystyle {#2} }{#1\textstyle {#2}}{#1\sc... l.6 Hello world! $\Ray{ABC} $. ? ! Emergency stop. <inserted text> $ <to be read again> \displaystyle \dodohandlemathoverarrow ...{\ialign {##\crcr #2#3 \crcr \noalign {\kern #1\n... \mathpalette ...>\mathchoice {#1\displaystyle {#2} }{#1\textstyle {#2}}{#1\sc... l.6 Hello world! $\Ray{ABC} $. (This is done with a live pdftex on the garden.) Any ideas? Thanks, Jesse -- Jesse Alama (alama@stanford.edu)