# [NTG-context] Stacking math symbols

Hans Hagen pragma at wxs.nl
Tue Feb 23 22:11:11 CET 2016

On 2/23/2016 7:31 PM, Nicola wrote:
> I find it a bit surprising that ConTeXt gives 'missing } inserted'
> with:
>
> \starttext\startformula
> \mathop=^{\rm def}
> \stopformula\stoptext
>
> (\mathop{=}^... is fine, though).
>
> The above formula is correct in Plain (Lua)TeX (in fact, it is
> copied from The TeX Book). Why does ConTeXt need braces?

this is because \mathop is redefined (in th eprocess assuming a braced
argument) ... this is a mkii leftover which is actually no longer needed
(mkii needed more tweaks to get fonts right)

you can add this to cont-new.mkiv

\let\mathop\normalmathop

but i'd use { } anyway

> (Before you point it out: I know that I should use \stackrel…)

don't worry ... i would not have thought of it (i never have to enter
that kind of math)

Hans

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