Hi,
this might be the same issue than one with \scantokens
which was discussed some time ago on this list (lost the reference)
\catcode0 12
\def\x {\romannumeral`^^@ foo bar foo bar foo bar}
\catcode0 9
\message{\meaning\x}
\immediate\write128{\meaning\x}
\bye
If I compile with luatex I get (there is a null character after `
in the first line and there is nothing after ` in second line)
(./testlualog.tex macro:->\romannumeral ` foo bar foo bar foo bar
macro:->\romannumeral `
)
in the log, whereas with pdftex I get
(./testlualog.tex macro:->\romannumeral `^^@ foo bar foo bar foo bar
macro:->\romannumeral `^^@ foo bar foo bar foo bar
)
Jean-François
