Hacker News with Generative AI: Type Systems

Nominal for Storing, Structural for Manipulating (bearblog.dev)
Something that comes up sometimes in programming languages is the difference between nominal and structural type systems.

Programming Languages, Type Systems

41 points by todsacerdoti 1 day ago | 30 comments

Adding row polymorphism to Damas-Hindley-Milner (bernsteinbear.com)
Damas-Hindley-Milner (HM) is a type system for Standard ML and the ML-family languages.

Programming Languages, Type Systems, Functional Programming

211 points by surprisetalk 29 days ago | 56 comments

Damas-Hindley-Milner inference two ways (bernsteinbear.com)
Damas-Hindley-Milner (HM) is a type system for the lambda calculus (later adapted for Standard ML and the ML-family languages) with parametric polymorphism, aka generic functions. It sits at a sweet spot in PL design: the type system is quite expressive, and there are well known type inference algorithms that require absolutely no annotations from the programmer.

Programming Languages, Type Systems, Lambda Calculus

139 points by todsacerdoti 37 days ago | 11 comments

A dictionary of single-letter variable names (jackkelly.name)
Haskell’s expressive type system means that type signatures can carry a lot of information. Haskell’s polymorphism means that you sometime write a function that works across an enormous range of types, and are often left wondering “what do I actually call my variables?”. It is often the case that there’s nothing to say beyond “this variable is a Functor”, or “this variable is a monadic action”, and so a single-letter variable name is appropriate.

Haskell, Programming Languages, Type Systems, Variable Names, Best Practices

110 points by todsacerdoti 40 days ago | 91 comments

Flux: Refinement Types for Rust (youtube.com)

Rust, Programming Languages, Type Systems

6 points by todsacerdoti 90 days ago | 0 comments

Higher-kinded bounded polymorphism in OCaml (2021) (okmij.org)

Programming Languages, Functional Programming, OCaml, Type Systems

141 points by tinyspacewizard 116 days ago | 10 comments

A type system for RCL, part 2: The type system (ruudvanasseldonk.com)

Programming, Type Systems, RCL

30 points by todsacerdoti 126 days ago | 8 comments

Counterexamples in Type Systems (counterexamples.org)