Bug#815205: another texinfo.tex bug in \scanmacro

[Gavin Smith]

On 17 March 2016 at 01:31, Norbert Preining <preining at logic.at> wrote:
>
> Ok, I tried your  suggestion, but that again breaks:

I've checked and using \gdef instead of \def works, because the
definition took place within a TeX group:

\input texinfo   @c -*-texinfo-*-

@iftex
@tex
\gdef\aaa#1{Hello #1}
@end tex
@end iftex

@macro bbb{word}
@tex
\\aaa{\word\}
@end tex
@end macro

@bbb{World}

@bye

I don't know why the original code used to work, because \gdef wasn't
used there either.

> Is this just an incorrect usage of macro definitions and @tex
> in the original sources, that "just happened" to work till 6.0,
> or is there something else behind?

There's nothing else to it as far as I can tell. As far as I know,
this usage has never been documented or encouraged. It appears to be a
recursive definition of a macro which actually uses a definition from
elsewhere.