Lambda the Ultimate

As seen on the Scala list, this video talks about how concurrency is easier to get done right in Scala. But the end part (starting around 46:13) was more interesting to me since it is Martin O. explaining how fubar things were and how hard it was to get all the types worked out just right such that code duplication and boilerplate could really be avoided.

[edit: one thing that i find interesting about it is the quip that "if only we had prolog built into our type checker" given that i'm waiting with bated breath for Shen to be released.]