More Change Tokens Crate

This library contains all of the fundamental abstractions for defining change tokens. Change tokens are used to signal changes to consumers via a registered callback. This library also provides a default change tokens:

• NeverChangeToken - will never change (e.g. Null Object pattern)
• SingleChangeToken - will change at most once
• SharedChangeToken - shareable change token across multiple owners
• AsyncSharedChangeToken - thread-safe, shareable change token across multiple owners

License

This project is licensed under the [MIT license].