GLML is an early stage functional domain-specific language for writing fragment shaders, targeting GLSL. Right now, it is primarily based on Hindley-Milner typing and features typeclasses for operator overloading. The long-term goal is to evolve into an ML-style language with size-dependent types.
Docs: www.glml-lang.com
Try GLML Playground: www.glml-lang.com/playground
