What is Haskell's equivalent to Rust's GAT?

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Haskell's equivalent to Rust's GAT is called TypeFamilyDependencies (TFD). TFD allows the definition of a type family whose parameters are dependent on other types in the family. This allows for the creation of higher-kinded types, which enable more complex and expressive type-level programming. However, TFD is not as powerful as GAT and does not allow for arbitrary type-level functions.