What is the "functional" way of doing this?

[Paul Rubin]

"attn.steven.kuo at gmail.com" <attn.steven.kuo at gmail.com> writes:
> Recursion is common in functional programming:
> 
> def f(n, l=None):
>     if l == None:
>         l = []
>     if n > 0:
>         return f(n/26, l + [n%26])
>     else:
>         return l
> 
> print f(1000)

Right, this is functional style, but quite painful in Python (no tail
recursion, and look at all that list copying).