Le 25/09/2011 10:06, Joseph Wright a écrit :
On 25/09/2011 08:13, Paul Isambert wrote:
Hello all,
The manual says catcode table 0 is initialized by INITEX. So you'd think
it holds INITEX catcodes. But actually it does absolutely nothing when
called:
\catcode`\$=14
\catcodetable0
\immediate\write17{\the\catcode`\$}% Prints 14.
\bye
Is that normal? I.e. is table 0 a noop on purpose?
Best,
Paul
Catcode table 0 holds the _current_ catcodes when the document starts:
it's never been saved using \savecatcodetable. You can't save the table
to itself, so the usual set up is to ave the IniTeX values to some other
table, then use a stack to switch out table 0 to the IniTeX one to 'do
stuff', then back again when the job is done. See for example Heiko
Oberdiek's 'luatex' package.
Thank you Joseph.
Indeed table 0 holds the document in force at the beginning of the
document. What confused me was actually something else, which I now see
as a real bug: when switching to a new table and then back to the
previous one, the latter seems to save the catcode changed while it was
active:
%%%
\savecatcodetable1 \savecatcodetable2
% Prints 3, fine:
\catcodetable1
\immediate\write17{\the\catcode`\$}
% Prints 14, fine:
\catcode`\$=14
\immediate\write17{\the\catcode`\$}
% Prints 3, fine:
\catcodetable2
\immediate\write17{\the\catcode`\$}
%Prints 14, not so fine:
\catcodetable1
\immediate\write17{\the\catcode`\$}
\bye
%%%
Ah, but this really gives me a headache, so I'd better get some input
here again before filing a bug report. I might have overlooked something.
Best,
Paul
