[gentoo-dev] USE_EXPAND is not an IUSE replacement [was: New USE_EXPAND: CLAWS_MAIL_PLUGINS]

[René Neumann]

Am 24.04.2013 11:51, schrieb René Neumann:
> As more and more packages seem to (mis)use USE_EXPAND: Can we get the
> possibility to set this directly in package.use? Having to write
> 'claws_mail_plugins_foo' does not help readability, and setting it in
> make.conf is also not the right way (as is package.env).

I just noted, that USE_EXPAND variables are even worse than I thought...

NGINX_MODULES_HTTP="-access" emerge -av nginx
Invalid '-' operator in non-incremental variable 'NGINX_MODULES_HTTP':
'-access

In other words: They do not even work from commandline (in a stacking
manner).

So, what exactly are the use-cases again, and why are normal use-flags
replaced by them? I already see a future where packages carry a
"FOOBAR_CONFIGURE_OPTIONS" use-expand ... when IUSE is not hip enough
any more.

- René

P.S.: Using USE_EXPAND for PYTHON_TARGETS or LINGUAS or VIDEO_CARDS is
of course good, as I (usually) set this system-wide.