Tag Archives: applicative

New Haskell Symposium paper on “twisted functors”

Satvik Chauhan, Piyush Kurur and I have a new paper which will appear at the 2016 Haskell Symposium in Japan: How to Twist Pointers without Breaking Them Although pointer manipulations are used as a primary motivating example, at heart the … Continue reading

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Teaching abstraction

I’m just beginning to prepare for the third incarnation of CIS 194, Introduction to Haskell in the spring. It’s occasioned some general thoughts on teaching abstraction which seemed worth writing down. Abstractions, of course, are everywhere in CS. By abstraction … Continue reading

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Parsing context-sensitive languages with Applicative

Many parser combinator libraries in Haskell (such as parsec) have both a Monad interface as well as an Applicative interface. (Actually, to be really useful, you also need MonadPlus along with Monad, or Alternative along with Applicative, in order to … Continue reading

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Monoids for Maybe

The other day I had two lists of monoidal values that I wanted to combine in a certain way, and I realized it was an instance of this more general pattern: > {-# LANGUAGE GeneralizedNewtypeDeriving #-} > import Data.Monoid > … Continue reading

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