Functional Programming: A PragPub Anthology

Beyond Haskell: Dependent Types

Haskell is something of a “sweet spot” in language design, balancing a reasonably flexible type system with useful inference properties, but it is by no means the best we can do. So what else is there?

Language designers continually experiment with modest extensions to Haskell’s basic system, to see if they can eke out any extra functionality without making the language too hard to use, and mileage varies here.

Instead, let’s look at the next big step in language sophistication, where we allow types to become full first-class citizens of our language. The Haskell we’ve seen so far still keeps the world of data separate from the world of types. Types are a description of happenings in data-land and they do ...