Why doesn't join() call str() on its arguments?

[Delaney, Timothy C (Timothy)]

John Roth wrote:

> result = "".join([str(x) for x in list])

As of 2.4, you should use a generator expression here instead (unless
you require backwards-compatibility with 2.3).

    result = ''.join(str(x) for x in iterable)

Easier to read, more memory-efficient, potentially faster (depending on
performance characteristics of building large lists).

Tim Delaney