[GHC] #974: Add unzipEithers, lefts, rights to Data.Either

[roconnor at theorem.ca]

On Mon, 13 Nov 2006, Bulat Ziganshin wrote:

> i prefer name splitEithers. for me, unzipping is process of splitting
> list of (a,b) values into the list of 'a' values and list of 'b'
> values - just like unzipping in real life. this don't have anything common
> with the algorithm of this function

The concern I have with split is that almost all the other split functions 
work by taking an ordered container and returning two containers where 
everything in the first container preceeds everything in the second 
container.  unzipEithers doesn't have this property.   However 
unzipEithers is a process of splitting a list of Either a b values into 
a list of 'a' values and a list of 'b' values, similar to the unzip 
function.

-- 
Russell O'Connor                                      <http://r6.ca/>
``All talk about `theft,''' the general counsel of the American Graphophone
Company wrote, ``is the merest claptrap, for there exists no property in
ideas musical, literary or artistic, except as defined by statute.''