# Package org.spongepowered.asm.mixin.injection.callback

Implementation of callback injector functionality provided by `@#64;Inject`.

- Interface Summary
  Interface | Description
  --- | ---
  Cancellable | Interface for things which can be cancelled

- Class Summary
  Class | Description
  --- | ---
  CallbackInfo | CallbackInfo instances are passed to callbacks in order to provide information and handling opportunities to the callback to interact with the callback itself.
  CallbackInfoReturnable<R> | For callbacks with a non-void return type, a CallbackInfoReturnable is passed to the callback instead to allow the callback to interact with the method return value.
  CallbackInjector | This class is responsible for generating the bytecode for injected callbacks, for details of usage see `@Inject`.

- Enum Summary
  Enum | Description
  --- | ---
  LocalCapture | Specifies the behaviour for capturing local variables at an injection point.

- Exception Summary
  Exception | Description
  --- | ---
  CancellationException | Exception thrown when a consumer attemtps to call `cancel()` on a callback not marked as `cancellable`.