Re: [RFC] Parametric Polymorphism

2005-09-26 Thread Bengt Richter
On Sun, 25 Sep 2005 09:30:30 +0100, Catalin Marinas <[EMAIL PROTECTED]> wrote: >Hi, > >Sorry if this was previously discussed but it's something I miss in >Python. I get around this using isinstance() but it would be cleaner >to have separate functions with the same name but different argument >ty

Re: [RFC] Parametric Polymorphism

2005-09-26 Thread Donn Cave
In article <[EMAIL PROTECTED]>, Catalin Marinas <[EMAIL PROTECTED]> wrote: ... > Of course, duck-typing is simple to use but the parametric > polymorphism is useful when the types are unrelated. Let's say you > want to implement a colour-print function which should support basic > types like ints

Re: [RFC] Parametric Polymorphism

2005-09-26 Thread Catalin Marinas
Tom Anderson <[EMAIL PROTECTED]> wrote: > Is there any reason you have to stringify the type signature? Types > are hashable, so a tuple of types is hashable, so you can just use > that as a key. Replace "methods[f.func_name][str(types)] = f" with > "methods[f.func_name][types] = f" and "type_str =

Re: [RFC] Parametric Polymorphism

2005-09-25 Thread Tom Anderson
On Sun, 25 Sep 2005, Catalin Marinas wrote: > Sorry if this was previously discussed but it's something I miss in > Python. I get around this using isinstance() but it would be cleaner to > have separate functions with the same name but different argument types. > I think the idea gets quite cl

Re: [RFC] Parametric Polymorphism

2005-09-25 Thread Benji York
Catalin Marinas wrote: > Sorry if this was previously discussed but it's something I miss in > Python. I get around this using isinstance() but it would be cleaner > to have separate functions with the same name but different argument > types. I think the idea gets quite close to the Lisp/CLOS > im

Re: [RFC] Parametric Polymorphism

2005-09-25 Thread Catalin Marinas
"Diez B. Roggisch" <[EMAIL PROTECTED]> wrote: > google for gnosis utils and multimethods to see a more "oldfashioned" > implementation. I now remember to have seen it but it requires a lot of typing to achieve it and you would call a different function name from the one you define, reducing the co

Re: [RFC] Parametric Polymorphism

2005-09-25 Thread Diez B. Roggisch
Catalin Marinas wrote: > Hi, > > Sorry if this was previously discussed but it's something I miss in > Python. I get around this using isinstance() but it would be cleaner > to have separate functions with the same name but different argument > types. I think the idea gets quite close to the Lisp/

[RFC] Parametric Polymorphism

2005-09-25 Thread Catalin Marinas
Hi, Sorry if this was previously discussed but it's something I miss in Python. I get around this using isinstance() but it would be cleaner to have separate functions with the same name but different argument types. I think the idea gets quite close to the Lisp/CLOS implementation of methods. Be