On śro, 2017-05-10 at 14:15 -0700, Patrick McLean wrote:
> On Wed, 10 May 2017 20:53:31 +0200
> Michał Górny <mgorny@gentoo.org> wrote:
> 
> > Allow two special values in the implementation patterns for
> > _python_impl_matches(): -2 to indicate all Python 2-compatible
> > implementations, and -3 to indicate all Python 3-compatible
> > implementations. Both of those values are implemented using
> > the python_is_python3 function.
> 
> Seems mostly reasonable, though the syntax is somewhat confusing at
> first glance. There are many places where we use "-value" to negate, so
> this looks like it means "not python 2" rather than "all python 2".
> Perhaps something like '+2' would make it easier to read.

Well, it was supposed to correspond to option parameters, so that it
doesn't collide with regular template matching. But '+' works for me
too, same as anything. Or '@2'. Or '${py2}' ;-P.

> 
> > This is mostly meant to make it easier and more fool-proof to write
> > dependencies on backports to Python 2 which in most cases apply to
> > PyPy2 as well.
> 
> 

-- 
Best regards,
Michał Górny