[fcantournet]

Every year someone figures out that encoding complex logic in type systems leads to complex type systems. YES. Types will not simplify your logic, they mean to represent it, in all its glorious complexity, in a way that is checkable automatically, and will break and require refectoring when you violate the previous invariants.

This is types working.

[SoftTalker]

This is also why I’m a fan of not-null constraints, check constraints, and foreign keys in my database schemas. They make (at least some) invalid states unrepresentable. And they work regardless of the front end application.

[wredcoll]

Checkable automatically is nice. Actually readable by humans is required.

Every year someone figures out that a program can pass the most rigorous compile time type checks and yet still be wrong.