On Tue, Mar 27, 2018 at 9:37 PM, Eric Gourgoulhon <egourgoul...@gmail.com> wrote: > Hi Simon, hi Erik, > > > Le mardi 27 mars 2018 21:09:08 UTC+2, Simon King a écrit : >> >> Hi Erik, >> >> On 2018-03-27, Erik Bray <erik....@gmail.com> wrote: >> > What about adding an optional argument to the is_prime() >> > method--something like a.is_prime(as_element_of=ZZ). It's kind of a >> > wordy (though I'm sure there's a more succinct spelling) way to write >> > ZZ(a).is_prime() but at least it's still precise about what you're >> > asking. >> >> I don't think it'd be a good idea. Reason: What should be the default >> value of "as_element_of"? Should it be the parent of "a"? But then, you >> immediately have the same problem as we have now, which is the >> surprising (to some) fact that (3/1).is_prime() returns False. And the >> work-around >> (3/1).is_prime(as_element_of=ZZ) >> would be more verbous than >> ZZ(3/1).is_prime() >> >> Best regards, >> Simon >> > > > Why not introducing a different function, is_prime_integer() say, keeping > is_prime() as it is now? > Of course, x.is_prime_integer(), or is_prime_integer(x), would return > ZZ(x).is_prime(). > Then, for the casual user, we should advertise (in examples, tutorials, > etc.) the use of is_prime_integer() over is_prime(). > Note that the casual user may discover is_prime_integer() by the standard > TAB mechanism, since its name starts by "is_prime". Facing the choice > between the two functions, he would probably (hopefully?) opt for > is_prime_integer(), which is self-explanatory.
+1 to Eric's idea. I think that should resolve the issue reasonably well, since for the "casual" user we're talking about it's integers they're probably concerned with--it doesn't need to become a slipper slope or anything. As a bonus, the curious undergrad will be surprised that there are separate is_prime and is_prime_integer and maybe learn something new. -- 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.
