algebraic-data-types

The defdata macro allows defining ADTs with multiple constructors (unary, binary, nullary), similar to Haskell, as shown with the maybe and liszt examples for clear data modeling.

Match provides compile-time warnings for non-exhaustive cases, such as when the polar case is omitted in point matching, enhancing code safety and reducing errors.

Optional mutability with :mutable t and set-data enables efficient in-place updates, useful for performance-critical code, demonstrated with the mirror-point! function.

The :include option lets ADTs inherit constructors from others, promoting code reuse, as seen with fuzzy-bool extending bool to add a fuzzy constructor.

get-constructors returns constructor names and arities dynamically, allowing for introspection and meta-programming, useful in debugging or dynamic systems.