Hi,
In plain TeX,
$$\smash{\sum_0^n}$$
is set in \displaystyle, just like
$$\smash{\sum_0^n}$$
However, ConTeXt
\starttext
$$\smash{\sum^0_n}$$
\stoptext
outputs the above in \textstyle, whereas
\starttext
$$\sum^0_n$$
\stoptext
is in (of course(?)) \displaystyle.
Is this difference intentional?
Thanks for reporting. I don't think it is intentional. (Can you show your real world example where \smash is needed? It seems to not really be used in any macro in ConTeXt.)
/Mikael
PS $$ is not meant to be used in ConTeXt. If you want inline math in display style, use \dm {}, and if you want displayed formulas in display style, use \startformula \stopformula.