flatten(), [was Re: map/filter/reduce/lambda opinions ...]

[Ron Adam]

> Ok...  How about a non-recursive flatten in place? ;-)
> 
> def flatten(seq):
>     i = 0
>     while i!=len(seq):
>         while isinstance(seq[i],list):
>             seq.__setslice__(i,i+1,seq[i])
>         i+=1
>     return seq
> 
> seq = [[1,2],[3],[],[4,[5,6]]]
> print flatten(seq)
> 
> I think I'll be using the __setslice__ method more often.


This is probably the more correct way to do it. :-)

def flatten(seq):
     i = 0
     while i!=len(seq):
         while isinstance(seq[i],list):
             seq[i:i+1]=seq[i]
         i+=1
     return seq