Re: configure.in: Look for flex

[Kevin Ryde]

address@hidden (Ludovic Courtès) writes:
>
> Since flex is needed when building from CVS and not needed when building
> from a distribution, what about something like the following:

I think AM_PROG_LEX probably does everything you need, with no
explicit warning code needed.  It looks like it sets up the "missing"
script to give a warning in those cases where lex is wanted.

> Then this means that the error message would only be triggered for
> people who passed the `--enable-maintainer-mode' option to `configure'
> (which /should/ be the case for people building from CVS, but I'm not
> sure this is actually the case since I didn't even use it myself ;-)).

If the generated file is checked into the cvs and the dates are right
then you won't need flex for a maintainer build, unless you actually
change the source.

(Maintainer-mode is mostly about regenerating configure, Makefile.in,
etc when the inputs change.)

> BTW, why is the flex-generated file included in the distribution?

Reducing dependencies (see "Releases" in the gnu standards manual),
apparently.