Am 20.10.2011 um 11:23 schrieb Javier Múgica de Rivera:
Note that the expansion of \directlua is a sequence of characters, not of tokens, contrary to all TeX commands. So formally speaking its expansion is null, but places material on a pseudo-file to be immediately read by TeX, as etex's \scantokens.
For a description of print functions look at section 4.13.10.
Is that really true? When you assign catcodes (catcode tables) to the print functions, >TeX's behavior is different from scantokens. I have never used scantokens, so I am >not 100% sure. Take for example:
tex.print(-2, "\\def\\foo{abc}")
will not define \foo. While you have referenced the section with the print commands, I >think that the description is misleading.
An so what is fed to TEX are characters, no tokens.
Thanks for the excellent in-depth explanation! No more questions. Patrick