List assignment, unexpected result

[Dave Reed]

> From: Paul Rubin <phr-n2002b at NOSPAMnightsong.com>

<snip>


> > The intent is clear i.e. fill the diagonal with 0,1,2,3; but the
> > result is somewhat different. Could anyone explain why this doesn't
> > work as expected - and even better, come up with an assignment for
> > 'grid' that would work.
> 
>   grid = [['.' * 4] for i in range(4)]
> 
> is one way.  


I think:

grid = [['.',] * 4 for i in range(4)]

is what you need otherwise you get: 
[['....'], ['....'], ['....'], ['....']]

and grid[1][1] gives you and index error

Dave