On Tue, Jun 7, 2016 at 10:36 AM, Jeroen Demeyer <jdeme...@cage.ugent.be> wrote: > On 2016-06-07 10:21, Erik Bray wrote: >> >> It's one thing to depend on a package at runtime. It's another thing >> to have a dependency just so that `./setup.py --help` can work without >> raising an ImportError :) > > > Well, could it be possible to arrange things such that Cython is needed at > *build-time* but only when actually building the package and not when doing > --help? That would be ideal.
Yes, but it's a pain in the butt to do and would require support from the setuptools end (without huge hacks, which astropy_helpers currently does). Maybe worth bringing up though... > The reason is that cythonize() does more than just converting .pyx files to > .c files. It can also change metadata of Extension classes, for example > changing the language to c++ or adding libraries to link against. For simple > projects with just a few Cython files, this might not be needed, but for > large projects like Sage, this is a very useful feature. I agree--I didn't realize that the old Cython.Distutils.build_ext doesn't do this. It's possible that whoever wrote the stuff in Cython.Distutils just hasn't maintained it (nor as anyone else). Using a custom setuptools command is still the way to go though, as I've demonstrated before. Erik -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
