Hindley-Milner Type System

The Hindley-Milner type system is a foundation for type inference in programming languages, particularly functional languages like Haskell and ML. It allows the compiler to automatically determine the types of expressions without requiring explicit type annotations from the programmer. This system uses a few simple rules to ensure that operations are used with compatible types, helping to catch errors early in the development process. Its ability to support polymorphism lets functions operate on different types, making code more flexible and reusable. Overall, it enhances code safety and readability while minimizing the need for type declarations.