[Haskell-cafe] lifting restrictions on defining instances

wren ng thornton wren at freegeek.org
Thu Jul 23 21:01:23 EDT 2009

John Lask wrote:
> Can anyone explain the theoretical reason for this limitation, ie other 
> than it is a syntactical restriction, what would it take to lift this 
> restriction ?

There are a couple of theoretical concerns, mainly that full type-level 
lambdas can lead down a rocky path (though simple combinators like 
`flip` and `const` are fine, and that's all we'd need for most cases). 
But by and large it's just a syntactic restriction.

Live well,

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