On Sat, Aug 1, 2009 at 3:18 PM, Simon King<[email protected]> wrote: > > Hi David, > > On 1 Aug., 23:55, David Joyner <[email protected]> wrote: >> 1. Be very very careful about modifying existing Python or Cython >> files in the Sage devel tree. > > Is it really allowed for an SPKG to modify things in the Sage devel > tree? This highly surprises me. I thought that an SPKG is a package, > and the word "package" suggests that it is packed, has an envelop, and > everything happens inside the envelop. > >> This will (AFAIK) affect every clone >> built after your spkg is applied and may make it difficult or >> impossible to create patches for the file(s) you changed. > > Yes, I think this would be a desaster, and thus tempering with devel/ > sage shouldn't be allowed. > >> 2. Be very very careful about modifying other existing spkgs. The spkg >> you touched my need to be reinstalled. However, without reading the >> install log, the person installing your spkg will not know what other >> spkg's were affected. (Example: The experimental 4ti2 overwrites >> Nathann Cohen's GLPK spkg with a much older GLPK. > > I remember being *explicitly* told that an spkg is not supposed to > install another spkg. And this is also stated in the developer guide, > if I remember correctly: If your package FOO depends on another > (optional) package BAR being installed, then FOO's install script > should test whether BAR is there. If it isn't, then the installation > of FOO should stop with an error, and the error message should of > course suggest that the user should install BAR first.
We could enforce this technically. I.e., then sage-env environment is setup a flag could be set so that, if "sage -i" is then run, one gets an error. William > > Again, the safety reasons are obvious, and I think I also remember > being told that licence problems might occur. For example, my > cohomology package depends on the SmallGroups library, but it would be > illegal for my (GPLv2+) package to automatically install the > SmallGroups library, since this is not GPLv2+ compatible. But it is ok > if the user installs the SmallGroups him/herself. > > I think that the problems David mentions should definitely be > addressed in the developer guide (and I think partially they *are* > addressed). > > Cheers, > Simon > > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
