[Haskell-cafe] Splitting off many/some from Alternative

[Gregory Crosswhite]

On Dec 13, 2011, at 5:09 AM, Bryan O'Sullivan wrote:

> Correct. And your example of "some (Just 1)" inflooping was not a counterargument, but rather an illustration that perhaps some people (and I'm not trying to imply you here, don't worry) don't understand what some and many are supposed to do.


But if you can't determine whether you can use certain methods of a typeclass without first knowing more about what type you are working with, then that breaks the abstraction since you can no longer treat a typeclass as a promise that given set of methods can be applied to a type.

Cheers,
Greg
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