Function Self

Do not ascend the container tree to resolve this identifier.

The constraints supported are listed in ResolutionConstraintFlag.

Example

This function can be used to construct a bitmask for use in the dependencies array of a service. While this can be used publicly, it is mainly for use within TypeDI; it allows you to configure specific constraints for use when resolving a specific service.

const constraintBitMask = Self();

if (constraintBitMask & ResolutionConstraintFlag.Self) {
  console.log('The dependency will not be resolved recursively.');
}
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Example

Here is an example of this constraint as part of a service declaration:

const NAME = new Token<string>('name');
const childContainer = Container.ofChild(Symbol());

@Service({ container: childContainer }, [
  [NAME, Self()]
])
class MyService {
  constructor (private name: string) { }
}

Container.set({ id: NAME, value: 'Joanna' });

childContainer.get(MyService);
// -> throws ServiceNotFoundError(Token<name>)
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Remarks

It is advised to combine this with Optional, as the usage of this constraint may mean that the identifier cannot be resolved.

See

ResolutionConstraintFlag