cangjie-type-system

Cangjie subtyping establishes type relationships through class inheritance, interface implementation, tuple covariance, and function contravariance or covariance to ensure predictable static type behavior.

Cangjie generics variance rules define covariant, contravariant, and invariant behaviors for user-defined generic types and built-in types, dictating how generic instances relate to each other.

Safe type casting in Cangjie uses the `is` and `as` operators, while explicit type conversions handle numeric types and Runes to ensure correct value transformations.

You need Cangjie type system variance rules when encountering complex generic type definitions or needing to ensure safe type casting to prevent runtime type errors.

Yes, Cangjie's static type system explicitly supports both tuple covariance and function contravariance or covariance simultaneously to govern complex type relationships safely.