Interactive code snippets not yet available for SoH 2.0, see our Status of of School of Haskell 2.0 blog post In the first Haskell Cast podcast Rein Henrichs and Chris Forno interviewed Edward Kmett in part about lens and it was suggested that Prisms don't have the same kind of introductory tutorial treatment. That's a shame, though. Prisms arise naturally all the time when using sum types. You co

What is Isabelle? Isabelle is a generic proof assistant. It allows mathematical formulas to be expressed in a formal language and provides tools for proving those formulas in a logical calculus. Isabelle was originally developed at the University of Cambridge and Technische Universität München, but now includes numerous contributions from institutions and individuals worldwide. See the Isabelle ov