Tag Archives: haskell

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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Species and Functors and Types, Oh My!

My paper on combinatorial species and the species library (an improved version of my previous ICFP submission) has been accepted to the 2010 Haskell Symposium! I look forward to seeing people in Baltimore in September, and in the meantime the … Continue reading

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Typed type-level programming in Haskell, part III: I can haz typs plz?

In Part II, I showed how type families can be used to do type-level programming in a functional style. For example, here is addition of natural numbers again: data Z data S n type family Plus m n :: * … Continue reading

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Improving GHC’s constraint solving

So I’ve been here at MSR Cambridge for almost two weeks now (!), working in the Programming Principles and Tools Group with Simon Peyton-Jones and Dimitrios Vytiniotis — and also collaborating with Stephanie Weirich and Steve Zdancewic, who are also … Continue reading

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Typeclassopedia in Japanese!

Satoshi Nakamura has published a Japanese translation of the Typeclassopedia. I don’t read any Japanese, but it sure looks cool, and I hope this will be a great resource for Japanese learners of Haskell. A big thank you to Satoshi … Continue reading

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Hac φ is underway!

Hac φ is now in full swing, with almost 20 people hacking away and more coming tomorrow. More news and pictures to come!

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Have you ever had a string like this “abc;def;ghijk;lm” and wanted to turn it into a list of strings, like this? [“abc”, “def”, “ghijk”, “lm”] Of course, you could always use a parsing library, or a regular expression library, but … Continue reading

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