[Haskell-cafe] ANNOUNCE: iterIO-0.1 - iteratee-based IO with pipe operators

wren ng thornton wren at freegeek.org
Sun May 8 03:53:03 CEST 2011

On 5/7/11 5:15 PM, dm-list-haskell-cafe at scs.stanford.edu wrote:
> In general, I try to place as few requirements in the contexts of
> functions as possible.

One counterargument to this philosophy is that there are many cases 
where fmap can be defined more efficiently than the liftM derived from 
return and (>>=). Similarly, the applicative operators (<*) and (*>) 
often admit more efficient implementations than the default.

So, when dealing with monads that have those more efficient definitions, 
you're restricting performance unnecessarily by forcing them to use the 
generic monadic definitions. There's nothing wrong with having multiple 
constraints in the context.

Live well,

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