Call operator for objc.ObjCBlock<ffi.Bool Function(ffi.Pointer<ffi.Void>, NSAlert)>.
objc.ObjCBlock<ffi.Bool Function(ffi.Pointer<ffi.Void>, NSAlert)>
Available on ObjCBlock<Bool Function(Pointer<Void>, NSAlert)>, provided by the ObjCBlock_bool_ffiVoid_NSAlert_CallExtension extension