why is Data.Set not a Monad?

[Daniel Franke]

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On Sun, May 06, 2007 at 07:44:53PM +0100, Frederik Eaton wrote:
> Anyone know why Data.Set is not a Monad? Or Data.Map?

I'm not sure why it ought to be.  I assume that you want
return = singleton and fail _ = emptySet, but how do you propose to
define (>>=)?

- -- 
 Daniel Franke         df at dfranke.us         http://www.dfranke.us
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