On 10/22/2016 08:08 AM, oldk1331 wrote: > Bill, I'm sorry that I give a bad example. > > About the axioms that "map" has to fullfill: > map(id, x) === x for all x > map(f, map(g,x)) === map(compose(f,g), x) for all x, f, g > > Of course it's possible to have a Functor(E) > for AbelianMonoidRing(R,E), it may not "make sense", > but it is doable, so it is important to have a documentation > for map in each domain that implements it.
I still don't like "Functor" as a name. And in fact "map" is also not the right name. But, naming aside... I'd rather would like to change the signature of "map" from map: (f: S -> S, %) -> % into map: (f: S -> S) -> (% -> %) and then it becomes clearer, that for a (categorial) functor F one would rather like to have: map: (f: A -> B) -> (F(A) -> F(B)) which somehow supports my dislike of the name "Functor". Am I wrong? Ralf -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/fricas-devel. For more options, visit https://groups.google.com/d/optout.
