Reimplementing xspace

[Giuseppe Bilotta <bourbaki@bigfoot.com>]

Hello,

this is another request from it.comp.software.tex: reimplementing
xspace. By itself the thing is pretty easy, you just need the
code:

\catcode`\@=11
\protected\def\xspace{\futurelet\@let@token\@xspace}
\def\@xspace{%
  \ifx\@let@token\bgroup\else
  \ifx\@let@token\egroup\else
  \ifx\@let@token\/\else
  \ifx\@let@token\ \else
  \ifx\@let@token~\else
  \ifx\@let@token.\else
  \ifx\@let@token!\else
  \ifx\@let@token,\else
  \ifx\@let@token:\else
  \ifx\@let@token;\else
  \ifx\@let@token?\else
  \ifx\@let@token/\else
  \ifx\@let@token'\else
  \ifx\@let@token)\else
  \ifx\@let@token-\else
  %\ifx\@let@token\@xobeysp\else %this would be
  %                              %nobreakspace
  \ifx\@let@token\space\else
  \ifx\@let@token\blankspace\else
   \space
   \fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi}
\catcode`\@=12

so the problem is rather on how to integrate this with the rest of
ConTeXt: there are some features of ConTeXt (e.g. logos,
abbreviations) for which obeying spaces should be an option. Right
now, you have to do something like:

\logo[tempTEX]{\TeX}
\def\TEX{\tempTEX\xspace}

to achieve the same result.

Any comments?