UInt32.(of|to)_int32 and UInt64.(of|to)_int64 functions.
Expose the type of the containing structure in boxed_field.
Fold over the fields of a structured type.
Expose field type function.
Tweak the declaration of offsetof's type.
Test folds over struct fields.
Test folds over union fields.
More efficient string view implementation.
Notes on closure finalisation.
Don't use functions introduced in 4.02 (e.g. Set.S.of_list) yet.