Human-readable aggregation of dates and spans?

[Bryan K. Wright]

Hi folks,

        I'm looking for a way to take a list of dates and
spans like this:

        Dec 1, 2009
        Dec 2, 2009
        Dec 3, 2009
        Dec 20, 2009
        Jan 5-7, 2010

and turn them into a human-readable expression like this:

        Dec 1-3 and 20, 2009, and Jan 5-7 2010

Does a module already exist that can do this?  

        Thanks for any advice.

                                        Bryan

-- 
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Bryan Wright              |"If you take cranberries and stew them like 
Physics Department        | applesauce, they taste much more like prunes
University of Virginia    | than rhubarb does."  --  Groucho 
Charlottesville, VA  22901|                     
(434) 924-7218            |         br...@virginia.edu
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