Classes

The primary purpose of ErrorIO (which conforms to ErrorType) is to attempt to standardize a method for coalescing multiple errors. For example, a task with multiple subtasks might return a Result<T> the error type of which is an ErrorIO containing multiple errors from multiple failed subtasks. ErrorIO implements SequenceType, CollectionType, ExtensibleCollectionType, and ArrayLiteralConvertible.

Due to current swift limitations, we have to include this Box in Result. Swift cannot handle an enum with multiple associated data (A, NSError) where one is of unknown size (A)