Rules and Rule Functions This chapter explains how to work with rules and rule functions. For documentation on catalog functions see Chapter 16, Functions Topics • Overview of Rules and Rule Functions • Adding a Rule • Rule Editor Reference • Adding a Rule Function • Rule Function Resource Reference • Using Variables and Functions in the Rule Editor • Using Priority and Rank to Control Order of Rule Execution • Using the Quick Fix Feature in the Rule Editor • Tips for Working in the Rule Editor • Event Preprocessors • Transaction Error Handler Rule Function