On Sat, Feb 9, 2013 at 6:58 AM, Rick Johnson <rantingrickjohn...@gmail.com> wrote: > I'm a bit unnerved by the sum function. Summing a sequence only makes sense > if the sequence in question contains /only/ numeric types. For that reason i > decided to create a special type for holding Numerics. This will probably > result in many complaints from lazy people who want to use only one Sequence > type, which holds mixed types, THEN jamb nothing but numeric types into it, > THEN have a sum method that throws errors when it encounters a non-numeric > type!!! I say, too bad for you.
Most assuredly not. The sum builtin works happily on any sequence of objects that can be added together. It works as an excellent flatten() method: >>> nested_list = [["q"], ["w","e"], ["r","t","u"], ["i","o","p"]] >>> sum(nested_list,[]) ['q', 'w', 'e', 'r', 't', 'u', 'i', 'o', 'p'] >>> nested_list [['q'], ['w', 'e'], ['r', 't', 'u'], ['i', 'o', 'p']] I'm not sure what your definition of a numeric type is, but I suspect that list(str) isn't part of it. ChrisA -- http://mail.python.org/mailman/listinfo/python-list
