A Swift package for a type Delta<Element> with three cases:
source(Element)target(Element)transition(source: Element, target: Element)
This Delta type represents an inclusive OR relation: Either a source element is available, or a target element is available, or both are available.
Delta behaves similar to Optional, but instead of representing 0 or 1 elements, it represents 1 or 2 elements.
The source and target are described as the two sides of a delta.
Both sides are accessible via optional source and target properties.
Convenient methods like resolve(favoring:) and merge(coalesce:) also provide access to the elements.
Transform a Delta value to a different Delta value using map(:), asyncMap(:), mapAny(:), or mapAll(:).
The Delta type also conforms to all standard protocols (depending on the conformances of it’s Element type):
EquatableHashableCustomDebugStringConvertibleEncodableEncodableWithConfigurationDecodableDecodableWithConfigurationSendableBitwiseCopyable~Copyable
Additionally, Delta conforms to RandomAccessCollection, allowing for iteration over the elements and many other operations provided by Sequence, Collection, and BidirectionalCollection.