Bill Pursell wrote:
> Georg Brandl wrote:
> > Paul Rubin wrote:
> > > Sybren Stuvel <[EMAIL PROTECTED]> writes:
> > >> Because of "there should only be one way to do it, and that way should
> > >> be obvious". There are already the str.join and unicode.join methods,
> > >
> > > Those are obvious???
> >
> > Why would you try to sum up strings? Besides, the ''.join idiom is quite
> > common in Python.
>
> One could extend this argument to dissallow the following:
> >>> "foo" + "bar"
It's worthwhile to note that the use of + as the concatenation operator
is arbitrary. It could just have well been | or &, and has no
relationship with mathematically addition. Were history different
perhaps Guido would have gone with | or & instead, and we wouldn't be
having this conversation.
It's also worth stressing (not in response to your post, but others)
that sum([[1],[2],[3]], []) is just as bad as attempting to sum
strings, both conceptually (it's not mathematical addition), and
performance-wise. Don't do it. :)
I believe the prefered method to flatten a list of lists is this:
shallow = []
for i in deep:
shallow.extend(i)
Yes, it's three lines. It's also very easy to read. reduce() and
sum() are not.
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