fp-ts Algebraic Data Types and Type Classes

Algebraic data types model complex domain logic in TypeScript by using product types for required data and sum types for mutually exclusive states. This approach enables safe composition and reusability across codebases using fp-ts utilities.

In domain modeling, product types represent data where all parts are required, like tuples and records. Sum types, implemented as discriminated unions, model mutually exclusive states and workflows to ensure valid domain transitions.

For TypeScript validation, fp-ts type classes like Eq, Ord, Semigroup, and Monoid provide utilities to implement flexible composition. They define equality, ordering, and combination rules for safe data structure handling.

Yes, you can pattern-match data structures built with fp-ts. Sum types, or discriminated unions, model mutually exclusive states and workflows, and pattern matching safely handles these exclusive states.

Yes, the fp-ts library is required. It provides the necessary Eq, Ord, Semigroup, and Monoid utilities to implement, compose, and pattern-match algebraic data types and type-class instances in TypeScript.

Avoid algebraic data types for API design when your domain lacks mutually exclusive states or required data compositions. ADTs are best suited for complex domain modeling and validation requiring safe composition.