A collection of interpreters, type checkers, and REPLs implemented in Haskell. Currently, the following languages are supported: Untyped lambda calculus SK combinator calculus System F Hindley-Milner type system Calculus of constructions You can access the different REPLs by passing an argument to the executable: "lambda", "sk", "systemf", "hm", or "coc". For more information, see the manual below.