Type Alias


A type alias to encapsulate the syntax for the completion handler block that's invoked after the request has finished processing.


typedef void (^VNRequestCompletionHandler)(VNRequest *request, NSError *error);


The completion handler is executed on the same dispatch queue as the request being executed.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

Learn more about using Apple's beta software