Companion
Functions
Answer the metatype for all function types. This is just an instance type on the most general type.
Answer a new function type whose instances accept arguments whose types conform to the corresponding entries in the provided tuple of types, produce values that conform to the return type, and raise no checked exceptions.
Answer a new function type whose instances accept arguments which, if collected in a tuple, match the specified tuple type. The instances of this function type should also produce values that conform to the return type, and may only raise checked exceptions whose instances are subtypes of one or more members of the supplied exception set.
Answer a new function type that doesn't specify how many arguments its conforming functions have. This is a useful kind of function type for discussing things like a general function invocation operation.
Answer the top (i.e., most general) function type.