identity ⋅ initial ⋅ terminal ⋅ mirror ⋅ record ⋅ option ⋅ derive ⋅ within ⋅ happen ⋅ that ⋅ this ⋅ supertype ⋅ subtype ⋅ basetype ⋅ boundtype ⋅ rewrap ⋅ wrapped