On May 27, 2017 11:32 AM, "Jeroen Demeyer" <jdeme...@cage.ugent.be> wrote:
Otherwise it sets `$(inst_<spkg>)` to a > dummy file that always exists (this way any dependencies for that > package are still satisfied, but the spkg is never actually > built/installed). > Let me mention *why* I came up with this dummy file: even if configure detects that a Sage package is not needed, it can still be explicitly installed by sage -i PKGNAME # This is essentially the same as "make PKGNAME" If I understand your proposal, if a system package is used, sage -i PKGNAME will *not* install the Sage package since the "spkg" is satisfied by the system package. Personally, I find it more intuitive if "sage -i PKGNAME" would unconditionally install the Sage package PKGNAME, even if PKGNAME was detected as system package I'll respond in more detail later but I agree with you completely here. By default, all packages would be installed from the sage-dist source > as is the case now. > I wonder why you propose this. The reason why we check for gcc for example is because we want to avoid building the Sage package if we can. If you go to the trouble of adding a check for system packages, the default should be to *not* install the Sage package if the system package works. This is the kind of detail that I think is arguable and why I wanted to write a long message explaining it :) The reason I proposed this was just to change as little as possible about the current behavior (something like GCC would be a special case). Another reason is that checking for every package would make configure take a lot longer, though I do think the results of those checks should be cached, so maybe most of the time it would not be too bad. I'd be fine with going either way. The --with-system-all option would basically be the behavior of checking for every package. The question is whether it should error if a package isn't found, or just build the sage-dist package. (Or there can be a flag for that behavior in which case the question is what the default should be). Apart from these two points, I totally agree with your post. Now to find a volunteer to implement all that :-) I'm volunteering! I just wanted to run the idea by people in detail first. 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.
