On Wed, Dec 26, 2018 at 6:26 PM Timo Kaufmann <eisfre...@gmail.com> wrote: > > Am Mittwoch, 26. Dezember 2018 01:25:59 UTC+1 schrieb Simon King: >> >> Hi Timo. >> >> On 2018-12-25, Timo Kaufmann <eisf...@gmail.com> wrote: >> > I don't really see a reason to rename it. The old name doesn't suggest that >> > it is implemented with pexpect. >> >> No, it does, by tradiation: >> AFAIK, *ALL* interfaces that are named after a third-party computer algebra
if you count ECL in, the interface with it is not pexpect, yet it is called ecl, not libecl. >> projects (gap, singular, r, pari, polymake, maxima, and of course magma, >> mathematica...) used to be pexpect interfaces. There has been >> an increased use of C level interfaces (libsingular, libgap, ...), but I got >> the impression that their names give a hint that they are not pexpect >> interfaces. > > > You're involved with the project. I doubt most users ever had a look at the > implementation. > >> >> For me, suddenly changing the gap or singular interface from pexpect to C >> would >> be a nasty surprise that would totally break my research code, because... >> >> > The implementation by definition should be n implementation detail, >> > the behaviour is largely the same. >> >> ... indeed this is (from my perspective) a weakness of libgap: >> libgap.__call__ >> is not equivalent to gap.__call__ and libgap.eval isn't equivalent to >> gap.eval. IMHO it is carelessness of the pexpect gap interface design: while there are perfectly reasonable GAP names for functions, e.g. Order() for the group order in GAP, available in libgap, Sages's pexpect gap has cardinality() etc. This is just unnecessary namespace bloat. And dont't get me started on DihedralGroup(k)'s meaning :-) >> Also the way we currently use libsingular is totally not the same as >> calling the singular pexpect interface. >> >> I don't know if the C interface to R behaves exactly like the pexpect >> interface. If they behave truely (not just *largely*!) the same, then of >> course a change from pexpect to C interface shouldn't matter very much. > > rpy2 also runs an R interpreter that behaves just as a REPL would, it just > communicates at an API level instead of parsing text. It behaves the same > (except were the old interface didn't work at all). The only edge case I'm > aware of has to do with help pages and that is fixed. > >> >> However, still I would be in favour of a deprecation: There should, for >> the reasons stated in other posts, be only a single instance of the C >> interface, called "r", replacing the current pexpect interface called >> "r" (provided that they behave the same). But for the time being, there >> should still be sage.interfaces.r.R so that R() results in a deprecation >> warning and returns a new instance of the R pexpect interface. > > > I still don't think there is a good reason to revive the pexpect interface. > Removing/deprecating `R()` sounds reasonable. I am for removal of pexpect interfaces for which there are replacements available. > >> >> Note that there may also be issues with pickling. Has it been possible >> to pickle objects defined via the pexpect R interface? If this is so, >> would the stored pickles automatically unpickle as C interface R >> objects? > > > No, that was also one of the things broken with the old interface: > https://trac.sagemath.org/ticket/26596#comment:38 > Also the internal sage objects are still the same (`RElement` etc). I suggest > that you play with it / read the ticket and see if there are actually > relevant differences. > > Regards, > Timo > > -- > 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. -- 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.
