Author Archives: Brent

About Brent

Assistant Professor of Computer Science at Hendrix College. Functional programmer, mathematician, teacher, pianist, follower of Jesus.

Submit to the Workshop on Type-Driven Development!

This year I am the co-chair (with Sam Lindley) of the Workshop on Type-Driven Development, affectionately known as TyDe1. The workshop will be co-located with ICFP in Oxford, and is devoted to the use of “static type information…used effectively in … Continue reading

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Deep work and email habits: a followup

About six months ago I wrote a post about some new work habits I adopted, inspired by Cal Newport’s blog and by his book, Deep Work. First, I began scheduling blocks of “deep work” time during the week, when I … Continue reading

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Signed sets and ballots and naturality

This is blog post #3 in a series on signed sets and ballots (the previous posts are here and here). Naturality, isomorphism, and equipotence When are two species isomorphic? Since species are, by definition, functors , the obvious answer is … Continue reading

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Signed sets and ballots, part 2

Recall, from my previous post, that our goal is to find a combinatorial proof showing the correspondence between signed sets and signed ballots, where a signed set is just a set of elements, considered positive or negative according to the … Continue reading

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Signed sets and ballots, part 1

The other day, Anders Claesson wrote a very nice blog post explaining a more combinatorial way to understand multiplicative inverses of virtual species (as opposed to the rather algebraic way I explained it in my previous post). In the middle … Continue reading

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Virtual species suffice

Over six years ago, I wrote a post explaining how virtual species are defined. Ever since then (time flies!) I’ve been meaning to write a follow-up post explaining a bit more about virtual species and how they actually suffice to … Continue reading

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Advent of code #16 solution: an algebra of bitstrings

I had fun this past December solving Advent of Code problems in Haskell. I was particularly proud of my solution to one particular problem involving generating and processing large bitstrings, which I’d like to share here. I think it really … Continue reading

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