a month ago
- The article discusses implementing data-directed programming in Haskell as seen in SICP 2.4.3, starting with tagged data and moving to an explicit operation table.
- It shows how to handle complex numbers in rectangular and polar forms using generic functions, and transitions to Haskell type classes for a cleaner, type-safe approach.
- The implementation allows for generic return types and uses existential types (AnyComplex) to create homogeneous collections of different representations.
- Type classes are compared to explicit dictionaries, highlighting compile-time safety and conciseness over Lisp's dynamic approach.