On Tue, May 28, 2013 at 10:00 AM, harry <voldermort@hotmail.com> wrote:

So so rephrase my question, why can't type classes be used as a type? Is

this an implementation issues, or is there a semantic problem with this?
Creating an existential type and packing all the values seems like busy work
which shouldn't be necessary, or at least something that the compiler should
be doing for me.

Haskell is strongly typed; if you want to throw out all the type information, you must tell if explicitly (which is what the existential does). This comes at a price, of course: once you've thrown out the type information, you can't get it back.

brandon s allbery kf8nh sine nomine associates

allbery.b@gmail.com ballbery@sinenomine.net

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