Template expression rules automatically set one or more parameters by formulas, parameter expressions. The trigger is a Boolean expression - the trigger expression. When the trigger expression becomes true the rule's parameter expressions are run in order from top to bottom.
Definition of trigger and actions
A template expression rule contains a trigger and one or more actions.
The trigger expression is a Boolean expression, and the rule is triggered when this expression becomes true. By default, the rule is triggered once when evaluation result of the trigger expression changes from false to true. An empty trigger expression is treated as always true.
The actions are one or more parameter expressions which are formulas for setting the value of parameters or multi choice values. These parameter expressions are executed in order from the top to the bottom of the list.
Note! Other rules are executed after the setting of each parameter. However, the template expression rule itself will not be triggered for the same configuration until all parameters have been set.
Clearing out values of parameters
A template expression rule cannot only set values of parameters it can also clear out parameter's values which means setting their values to null. This is done by adding parameters to the list of parameters to be set but without giving them a formula. For Boolean parameters and multi choice values indeterminate is the null value, i.e. neither true nor false.
Behavior settings
Template expression rules have settings that control their behavior:
Setting name |
Description |
|---|---|
Trigger continuously |
The template expression rule triggers every time the server executes rules as long as its trigger expression remains true, not only when the trigger expression changes from false to true. Note! Template expression rules without trigger continuously are not triggered when opening a saved configuration since they are only triggered when the evaluation result of the trigger expression switches from false to true during a configuration session. |
Read also about site effectivity for rules.
