Rules and methods supported by a collection

Call a rule or method from a collection to help model business decisions in your application. For example, you can call a decision tree in a step and then pass the results to a function for further analysis.

This functionality is available in:

The Action section of each step on the Rules tab.
The Update task modal, which can be launched from:
- The Response actions section on the Rules tab.
- The Before This Collection section on the Pre/Post Actions tab.
- The After This Collection section on the Pre/Post Actions tab.

The context of a collection step can restrict the available options you see when you call a rule or method.

Calling a rule or method

Select a rule type or method from the Type drop-down list.

The majority of the options prompt you for the name of the rule to call in the Name field. If applicable, additional fields appear for you to pass parameter values to the rule or method. Collections always pass parameters by value.

Rules that support return values automatically set the value of param.pxReturnValue when they complete processing. You can use the Copy return value to field to save this result and then evaluate it in a later step or response action.

Note: The Collection form reuses assembler logic for activities. Many options in the table below are equivalent to calling an activity method or instruction.

Rule type	Guidance
Activity	Equivalent to a Call instruction in an activity. The option to Pass current parameter page is not supported.
Collection	Equivalent to a Collect instruction in an activity. The option to Pass current parameter page is not supported.
Data Transform	Equivalent to the Apply-DataTransform method.
Decision Table	Equivalent to the Property-Map-DecisionTable method. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. This option is only available for a step in a collection.
Decision Tree	Equivalent to the Property-Map-DecisionTree method. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. This option is only available for a step in a collection.
Expression	Use the Target property field to call a declare expression with a key part that matches the specified property. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. You can only call declare expressions that use a calculate value of When applied by a Rule Collection. All other calculate values are not supported.
Function	Click and select a function alias. This list is populated with function aliases that return a void or boolean value. Enter values in the parameter prompts for the selected function alias. You can pass additional parameter values when the Get params button is visible. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. Your list of referenced rules is updated when the underlying function has parameters mapped to rule types.
Map Value	Equivalent to the Property-Map-Value method. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. This option is only available for a step in a collection.
Set Property	Equivalent to the Property-Set method.
Stop	Select an option in the Scope drop-down list to stop one or more collections in the call stack. Two stop methods are supported: This collection rule — Stops the current collection only. The post-actions specified on the Pre/Post Actions tab are processed before control returns to the calling collection or activity. Collection processing — Stops this collection and all other collections in the call stack. If the system finds an activity as it traverses the call stack, the stop method exits. You cannot call the stop method in a response action or post-action.
When	Enter the name of a when condition in the Name field. Use the Copy return value to field to store the value of `param`.pxReturnValue in the specified property. This option is available only for a step in a collection.

You can enter a period followed by the name of a property in the Name field. At run time, the system calls the rule name that matches the value of the specified property.

About Collections

Completing the Pre/Post Actions tab of the Collection form

Completing the Rules tab of the Collection form

Methods and instructions by name

Open topic with navigation

Rules and methods supported by a collection

Calling a rule or method

Rule type

Guidance