Deferred Evaluation

Example of user control of Deferred Evaluation in A++/P++. Deferred Evaluation is a part of A++ and P++, though it is not well tested in P++ at present.

xxx Deferred_Evalua (Set_Of_Tasks Task_Set; 		 		 		 build an empty set of tasks 
Deferred_Evaluation 		 		 (Task_Set) 		 start deferred evaluation 
		 {  
		 B = 0; 		 		 array operation to set B to zero - DEFERRED 
		 A = B + C; 		 		 array operation to set A equal to B plus C - DEFERRED 
		 }  
Task_Set.Execute(); 		 		 		 now execute the deferred operations