Patterns in Types: A Look at Reader, Writer and State in Scala

Developers are often very good at spotting repetition in their programs at the value level, but for some reason struggle, or are reluctant to apply that same careful analysis at the type level. This talk aims to build up an intuition for spotting when you can factor your types, examining what this gains you and looking at the practicalities for doing so in Scala. For appropriate buzz-word compliance during this talk you will see Scalaz, Monads, Monad transformers, data types and type classes.