Iterate over all pairs of consecutive items in a list

Given a list

    l = [1, 7, 3, 5]

I want to iterate over all pairs of consecutive list items (1,7), (7,3), (3,5), i.e.

    for i in xrange(len(l) - 1):
        x = l[i]
        y = l[i + 1]
        # do something

I would like to do this in a more compact way, like

    for x, y in someiterator(l): ...

Is there a way to do do this using builtin Python iterators? I'm sure the itertools module should have a solution, but I just can't figure it out.

Just use zip

    >>> l = [1, 7, 3, 5]
    >>> for first, second in zip(l, l[1:]):
    ...     print first, second
    1 7
    7 3
    3 5

As suggested you might consider using the izip function in itertools for very long lists where you don't want to create a new list.

    import itertools

    for first, second in itertools.izip(l, l[1:]):


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