[Haskell-cafe] Eq Type Class: Overloading (==)

Jason Dagit dagit at eecs.oregonstate.edu
Sat Sep 17 15:36:06 EDT 2005

On Sep 17, 2005, at 1:43 AM, Bulat Ziganshin wrote:
> about making Bool a class - it is the same issue as making
> head/map/... belonging to some Collection class. we need to change
> standard Prelude or add to Haskell "supertyping" mechanism, proposed
> by John Meacham, as i remember

A link to supertyping can be found here:

After reading that, I wonder why it's not implemented.  It seems like  
a wonderfully useful idea.  I view it as a way to add things back to  
the language which should have been there to begin with, but which  
the language designers left out for various reasons (such as lack of  
time, interest or possibly even oversight).


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