The Hazy Haskell Compiler

Today is my birthday and I’d figure I would celebrate by giving a progress report on Hazy.

Here’s a quick list of what I’ve done over these past 3 months

• Syntax sugar
  • Lambda expressions
  • Case expressions
  • Lambda case expressions
  • Let pattern binding
  • Integer literals
  • Floating point literals
  • Do notation
  • Right sections
  • Type annotation expressions
• Language features
  • Default methods
  • Monomorphic generalization
  • Newtypes
  • Strict fields
• Library / Tooling
  • A significant part of the Prelude has been implemented
  • A bare minimum package format for saving and loading sets of modules

I also have another new extension: LevityPolymorphicFields. You can now parameterize a field by it’s strictness.

type List :: Levity -> Type -> Type
data List s a
  = Nil
  | Cons
      { head :: ~!s a,
        tail :: ~!s (List s a)
      }

Here List Strict a would be a fully strict list while List Lazy a would be a lazy one. I have more details in my readme.

Of course all of this isn’t enough for Hazy to be usable yet as there’s still some missing parts, but I am getting a lot closer.