Re: [Haskell-cafe] Associated data types

Hi.

Date: Wed, 10 Dec 2008 13:36:11 +0000 From: Lennart Augustsson Subject: Re: [Haskell-cafe] Associated data types

For an associated data type D, we know that the type function D is injective, i.e., for different indicies given to D we'll get different data types. This makes much more powerful reasoning possible in the type checker. If associated data types are removed there has to be some new mechanism to declare an associated type as injective, or the type system will lose power.

-- Lennart

2008/12/10 Eyal Lotem :

...

If we have associated type synonyms, is there still reason to have associated data types?

[...] Another, somewhat related, issue is that associated type synonyms cannot currently be partially applied, whereas associated data types can. Cheers, Andres -- Andres Loeh, Universiteit Utrecht mailto:andres@cs.uu.nl mailto:mail@andres-loeh.de http://www.andres-loeh.de