give equal rights to types and classes! :)

Bulat Ziganshin bulatz at
Sat Feb 4 05:48:56 EST 2006

Hello Marcin,

Saturday, February 04, 2006, 2:23:50 AM, you wrote:
>> if my idea was incorporated in Haskell, this change don't require
>> even changing signatures of most functions working with arrays -
>> just Array type become Array interface, what a much difference?

What would 'Eq -> Eq -> Ord -> Bool' mean?
MQK> '(Eq a, Eq b, Ord c) => a -> b -> c -> Bool'?
MQK>       '(Eq a, Ord b) => a -> a -> b -> Bool'?
MQK>       '(Eq a, Ord a) => a -> a -> a -> Bool'?

as i stated in the post, the one class name instantiates one variable.
so the proper variant will be second

i know that this syntax can't substitute ALL possible uses of
preconsitions, it's just for most common, in my sense. moreover, it
will help to convert currently used types to classes, and to easily
refactor user programs back and forth between using types and classes

Best regards,
 Bulat                            mailto:bulatz at

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