# [NTG-pdftex] Extensions: \pdf$foo or \$foo?

Hans Hagen pragma at wxs.nl
Thu Jun 30 13:01:38 CEST 2005

Martin Schröder wrote:
> Hi,
> at LinuxTag in Karlsruhe I met with Heiko and Hartmut and we
> talked about pdfTeX. One point discussed was namespace: Till
> lately most new primitives of pdfTeX startet with \pdf (\efcode,
> \lpcode and \rpcode are the only exceptions), but now we have
> (\leftmarginkern, \rightmarginkern, \elapsedtime, \resettime,
> \random). I'm reluctant to use the non-\pdf-namespace and think
> it better to stay in \pdf.
>

this is why i wrote a while ago that we need a different prefix, something

\etxelapsedtime

on the other hand thereis hardly any chance for a clash, e.g. if a macro package
defines \elapsedtime it will still work ok; of course when one in such a macro
package wants access to the original primitive, one can save its meaning; this
is what i normally do.

\let\normalelapsedtime\elapsedtime
\def\elapsedtime{.... \normalelapsedtime ...}

what we actually need is some access to the original meaning, like
\primitive\elapsedtime; i dunno how hard it is to implement

\def\elapsedtime{.... \primitive\elapsedtime ...}

personally i think that we should move forward and not clobber extensions with
funny prefixes as in \pdfleftmarginkern and such; as said, if a macro package
wants to use that features, it has to be pdftex aware and as such can take
measures to save the original meaning

(so we could also argue for removing all \pdf prefixes)

(when etex came available, it introduced primitives that clashed with low level
context ones; it never was a real problem; one simply cannot extend tex and take
all packages into account)

Hans

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