extended list comprehensions

[Greg Ewing]

Andrew Dalke wrote:
> 
> y = "prefix-"
> {y=y+x for x in xs}
> 
> But given that, if y doesn't exist before the {} is called, your
> argument is that it should implicitly be set to 0.  This then would
> be one of the few places in Python with a default value, outside of
> a function parameter definitions.

Hmmm, maybe something like

   (y = y + x for x in xs from y = 0)

Or maybe not. I think this sort of thing is just
too rare to be worth a special syntax, as much
fun as it may be devising one!

-- 
Greg Ewing, Computer Science Dept, 
University of Canterbury,	  
Christchurch, New Zealand
http://www.cosc.canterbury.ac.nz/~greg