Functional Mode

Functional mode requires a top expression to be assigned to the function. During processing, the function triggers and evaluates the top expression. The top expression may use a number of nested expressions to find a result. The result of the top expression is the result generated for the function. For example, a decision table can be assigned as a top expression to a function. The context data objects are used as input for those columns of the decision table that are used for formulating the conditions. As a result, the decision table nests a formula expression. The result of the decision table is returned as the function result. Typically, the functional mode is used for more simple use cases with a clear output of the function.

Event Mode

Event mode uses rulesets to trigger processing instead of a top expression. A function can have numerous rulesets assigned. Each ruleset contains a number of rules. A rule consists of a condition and an action part. These rules with additional restrictions determined by preconditions, time dependency, enabled/disabled status are triggered when the function is processed. If a rule condition is satisfied, the action is processed. An action can simply change the values in the context or initiate additional activities, such as starting a workflow or writing error messages to a log. All the actions that are performed while the function is executed are collected in the predefined Actions table that is automatically used as the function's result data object in event mode.

Rulesets may also contain other expressions such as decision table or formula expressions. Typically, event mode is used for more complex use cases and for use cases where a result is not needed.

Functional and Event Mode

Functional and Event mode is a combination of functional mode and event mode. As with functional mode, assigning a top expression and a result data object is mandatory. In addition, rulesets can be processed so that actions can be performed, thereby possibly changing the context. At runtime, the function starts processing the assigned top expression. Once the expression evaluation is finished, function execution continuous with the associated rulesets.