# [Dev-luatex] The explanation of \directlua in the manual

Patrick Gundlach patrick at gundla.ch
Thu Oct 20 11:35:57 CEST 2011

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