# Spacing in commands for math mode

I would like to define commands with semantics similar to e.g. + in math mode. For instance,

$(x+y)$


produces an equation with some spacing around +, whereas

$(+)$


produces an equation with less (or no) spacing around +.

The reason is that I would like to write something like

$\token{repeat} \token{skip} \token{until} b$
$\token{skip}$


Where tokens are follwed by a space in the first case, but are not in the second. In a way, I'd like something similar to xspace, in math mode.

Any suggestions?

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+ gets it space from being a \mathbin but \mathbin{\hbox{#1}} doesn't do what you want.... – David Carlisle Sep 7 '13 at 11:21

## 1 Answer

Perhaps mathop spacing is what you are looking for.

\def\token#1{\mathop{\hbox{#1}}}

.$\token{repeat} \token{skip} \token{until} b$.

.$\token{skip}$.

\bye


\DeclareMathOperator in amsmath package for LaTeX.

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