This workflow is a GWorkflowDL representation of a cancelling discriminator that cancels the invocation of B if A has been executed and vice versa. This is only one out of various possibilities to model this workflow pattern. Please regard that this workflow example uses a separate method for cancelling the invocation of the activity. This is very useful if the invocation of the activity is done asynchronously as it is often implemented for long running methods. It may be necessary to propag...