On Saturday, July 19, 2014 5:43:57 AM UTC-7, defeo wrote: > However, Julia multimethods are backed up by a powerful coercion > system, so I do not understand the "step back" criticism. > > That comment wasn't made with respect to Julia, because that would be comparing the coercion facilities of a CAS to those of a programming language. Coercion in a CAS tends to be a *lot* more complicated than what programming languages are designed for. As an example:
Consider A+B where A is a polynomial in ZZ[x,y] and B is a power series in F_q[[x]] (finite field with q elements). Do you expect your CAS to make sense of that addition? Sage does. It returns an answer in F_q[[x]][y] (i.e., a polynomial in y over power series in x over F_q) . You can argue whether it's desirable for a system to try to be that smart, but all computer algebra systems I know are a "step back" relative to this. Programming languages do not tend to have type models that would even allow you to try and make sense of this kind of question. -- 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/d/optout.
