On Sat, Jul 13, 2013 at 5:50 AM, Nicolas M. Thiery <nicolas.thi...@u-psud.fr> wrote: > Hi all, > > Thanks Darij for bringing up the issue, and everyone for your > feedback! Here is my (strong for once) opinion on this issue.
+1 to everything in your strong opinion. > Sorry I > am taking off right now for vacations, so it's stated in a rush. > > - I for myself usually prefer left composition for permutations (like > most combinatorialist) but do prefer right actions in many other > related situations. In short, I want both :-) > > - GAP (and to a lesser extent Magma) is *the* reference when it comes > to computational group theory. I find it very natural that Sage > chose to follow GAP's lead. > > - A global option for this is bad. In general, global options should > not affect the semantic. > > - +1 on a parent option: > > sage: PermutationGroup(..., action='left') > > Note that this is consistent with what we do for finite set maps: > > sage: M = FiniteSetMaps([1, 2, 3], action = 'right') > > Maybe PermutationGroupElement will need to take an option too, and a > decision will need to be taken for mixed products. > > - -1 on changing the default value. There is way too much risk to > break user code out there and in a way to subtle way. > > Cheers, > Nicolas > -- > Nicolas M. Thiéry "Isil" <nthi...@users.sf.net> > http://Nicolas.Thiery.name/ > > -- > 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 http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/groups/opt_out. > > -- William Stein Professor of Mathematics University of Washington http://wstein.org -- 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 http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/groups/opt_out.
