Alissa Pajer’s (@alissapajer) FlatMap Oslo’s talk starts curiously with “Yoneda Yay!” - so you know it’s going to be good. But, is this a category theory talk, or something about Haskell? Both, of course! Alissa shows us how learning Haskell strengthens our understanding of abstractions as it makes certain concepts more obvious. It also forces us to think more clearly about our abstractions.
The Yondea Lemma is a concept that explores the equivalence between two types, that is, types that can be tranformed from one type into another without losing information. She explains it way better.
Alissa knows her stuff; she has studied pure mathematics and currently employs her functional programming skillz at RichRelevance.