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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 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.

Collection

Equivalent to a Collect instruction in an activity.

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 the Down arrow icon 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.