Question on lists

[Andrew Bennetts]

On Wed, Jul 28, 2004 at 03:26:54AM +0000, Kristofer Pettijohn wrote:
> My question is about lists:
> 
> Is there a way to remove duplicate items from a list that are
> next to each other?
> 
> Example...
> 
> Performing the operation on ['a', 'b', 'c', 'c', 'd', 'd', 'd', 'e']
> will return ['a', 'b', 'c', 'd', 'e']
> 
> Performing the operation on ['a', 'b', 'c', 'c', 'd', 'c', 'd', 'e']
> will return ['a', 'b', 'c', 'd', 'c', 'd', 'e']
> 
> I'm guessing there is probably nothing internal that will do it, so
> I may have to write something on my own - just thought I'd check
> first ;)

Nothing builtin that I know of, but it's trivial to write:

    def uniq(iterable):
        """Remove consecutive duplicates from a sequence."""
    
        prev = object()
        for element in iterable:
            if element != prev:
                prev = element
                yield element

    >>> list(uniq(['a', 'b', 'c', 'c', 'd', 'd', 'd', 'e']))
    ['a', 'b', 'c', 'd', 'e']
    >>> list(uniq(['a', 'b', 'c', 'c', 'd', 'c', 'd', 'e']))
    ['a', 'b', 'c', 'd', 'c', 'd', 'e']

-Andrew.