[texhax] Ref. Man. Bausum [was tabbing]
Philip TAYLOR
P.Taylor at Rhul.Ac.Uk
Fri Sep 15 01:16:54 CEST 2006
Uwe Lück wrote:
> I know very well about TeX primitives and the asterisk.
> Some misunderstandings seem to lurk here.
> Example: Consider a TeX version TeX- that agrees
> with TeX let alone the fact that TeX- doesn't have
> the primitive \gdef. TeX- then behaves like TeX
> if you include \def\gdef{\global\def} in your macros.
No, it does not. Here is a short example which
first uses the primitive \gdef and then uses
a macro \gdef which expands to \global \def :
\def \skiponetok {\let \next = }
\long \def \foo #1{#1\par}
\expandafter \skiponetok \gdef \foo {bar}
\message {\meaning \foo}
\def \gdef {\global \def}
\long \def \foo #1{#1\par}
\expandafter \skiponetok \gdef \foo {bar}
\message {\meaning \foo}
\end
Now here is the log file which it produces :
notice the difference between the behaviour of
the primitive and the behaviour of the macro :
This is pdfeTeXk, Version 3.141592-1.30.3-2.2 (Web2c 7.5.5)
(format=tex 2006.1.26) 15 SEP 2006 01:09
**uwe.tex
(./uwe.tex \long macro:#1->#1\par macro:->bar [1] )
Output written on uwe.dvi (1 page, 224 bytes).
Philip Taylor
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