The GREPLY.CMD sample in the \TOOLKIT\SAMPLES\REXX directory demonstrates the difference between Guarded and UnGuarded methods. In the first example, the method is guarded, so it does not begin execution until the final result is tallied. In the second example, the method is unguarded so it can begin execution while method sum_up is still looping. In fact, unguarded_get often runs immediately after the Reply, so using a guard instruction ensures sum_up runs for a bit before unguarded_get returns with the intermediate sum.

For this sample to function properly, Object REXX must be installed.