20

I am aware of the difference between using \(...\) and $...$ (in moving arguments, for example), and yes, I've read the answers to this question: Are \( and \) preferable to $?). I also know the definition of \( and \):

 \def\({\relax\ifmmode\@badmath\else$\fi}
 \def\){\relax\ifmmode\ifinner$\else\@badmath\fi\else\@badmath\fi}

(taken from Section 55.2 of source2e.pdf)

My question here is: couldn't \( and \) have been defined as robust commands in the LaTeX kernel? Is there any (non trivial) reason explaining why they were defined as fragile commands?

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Gonzalo Medina
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1 Answers1

21

Since the fixltx2e package ends with

\MakeRobust\(
\MakeRobust\)
\MakeRobust\[
\MakeRobust\]
\MakeRobust\makebox
\MakeRobust\savebox
\MakeRobust\framebox
\MakeRobust\parbox
\MakeRobust\rule
\MakeRobust\raisebox

it is probably safe to say that it was simply a mistake that was left around because the kernel can't change at this point. It's also worth pointing out that this is covered in Section 4 in the fixltx2e documentation titled “Fixes added for 2005/12/01.”

TH.
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