KM020B3: ERROR_TextBeforeOrAfterNulInOutput

If a rule has nul in the output, it means that it deletes any context referenced on the left-hand side of the rule, and has no other output, so it does not make sense to have any content apart from the nul statement in the output.

The following statements can still be used with nul in the output:

• beep()
• call()
• reset()
• return
• save()
• set()
• use()