The article introduces a Dart 3.0 pattern using final classes with private constructors to create 'proof types'—types that serve as computational witnesses ensuring certain validations or checks have occurred before an instance can be created. This leverages Dart's library-scoped privacy and sound type system to enforce correctness at compile time.
Background
This technique exploits Dart’s access control and type safety to encode validation logic into the type system, preventing invalid states from being represented in code. It aligns with dependently typed programming concepts but within Dart’s existing constraints.
- Source
- Lobsters
- Published
- Jul 29, 2026 at 06:30 AM
- Score
- 7.0 / 10