What is the most efficient way to do this?

[Skip Montanaro]

    mdk> What is the most efficient way to remove empty items from this
    mdk> list? 

    mdk> ['', '1', '2', '3', '', '456', '789', 'wow']

I'll give you a couple options and let you worry about efficiency...

    >>> l = ['', '1', '2', '3', '', '456', '789', 'wow']
    >>> filter(None, l)
    ['1', '2', '3', '456', '789', 'wow']
    >>> [x for x in l if x != '']
    ['1', '2', '3', '456', '789', 'wow']
    >>> while '' in l:
    ...   l.remove('')
    ... 
    >>> l
    ['1', '2', '3', '456', '789', 'wow']

Note that the first two ways create new lists and leave l untouched.  The
third way modifies l in place.

-- 
Skip Montanaro (skip at pobox.com - http://www.mojam.com/)