Tag Archives: types

Unordered tuples and type algebra

At Hac Phi a few weekends ago (which, by the way, was awesome), Dan Doel told me about a certain curiosity in type algebra, and we ended up working out a bunch more details together with Gershom Bazerman, Scott Walck, … Continue reading

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Typed type-level programming: status report

A few people have been bugging me (you know who you are ;-) about the current status of the project to allow automatic “lifting” of Haskell data constructors to the type level, to allow for typed type-level programming. I’ve written … Continue reading

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On a Problem of sigfpe

> {-# LANGUAGE TypeFamilies, EmptyDataDecls, TypeOperators, GADTs #-} At the end of his most recent blog post, Divided Differences and the Tomography of Types, Dan Piponi left his readers with a challenge: In preparation for the next installment, here’s a … Continue reading

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Typed type-level programming in Haskell, part IV: collapsing types and kinds

In Part III, we saw how the current state of the art in Haskell type-level programming leaves some things to be desired: it requires duplicating both data declarations and code, and even worse, it’s untyped. What to do? Currently, GHC’s … Continue reading

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Typed type-level programming in Haskell, part II: type families

In my previous post, we saw how multi-parameter type classes with functional dependencies in Haskell allow us to do type-level programming in a logic programming style. (If you’re not clear on why this corresponds to a logic programming style, see … Continue reading

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