Jane Street has been writing production software in OCaml, a functional language, for over a decade. We are to our knowledge the world's largest industrial user of functional languages. Billions of dollars worth of financial transactions flow through our functions and modules every day.
This talk will summarise our view of the relative importance of the features of OCaml and other similar languages. In particular, we will contrast with Hughes' seminal paper, "Why Functional Programming Matters". While we don't disagree with Hughes' view that statically typed functional languages are unusually effective tools, we'll argue that an expressive static type system, which Hughes doesn't mention, should be near the top of the list, and purity, which many think of as the defining aspect of functional programming, is near the bottom.
About the lecturer:
Sebastian Funk joined Jane Street after graduating from the University of Cambridge with a special focus on type theory and functional programming. He has since been working on building trading systems in OCaml, making every-day use of the tools presented in this talk.