Creating or Editing Expression Rules

You can use the interactive expression editor to create or edit a complex expression rule. An expression rule defines valid, invalid, and required selections for specific combinations of variants, variant values, and options for the model version. You must create expression rules before a model version reaches the Frozen state.

This task shows you how to:

Create an Expression Rule

Before you begin: Do the following:
  1. Create the model version. For more information, see Creating a Model Version.
  2. Open the model version. For more information, see Opening a Model Version.
  3. Allocate its variability. For more information, see Allocating Variability to a Model Version.
  1. Select the Rules tab.
  2. From the page toolbar, select New > New Expression Rule.
  3. Enter a title for the new expression rule.
  4. Optional: Enter a description of the expression rule.
  5. Optional: To select an image for the new expression rule, do one of the following:
    OptionActions
    Drop imageDrop an image into the Image field.
    Upload Image
    1. Click Upload Image.
    2. Browse to, then select the image.
    3. Click Open.
  6. To create the expression rule, do one of the following:
    OptionActions
    Create a Single Expression Rule Click Create.
    Create Multiple Expression Rules Click Create another.

    Your expression rule is created. The dialog box remains open so that you can create another expression rule by changing the information.

Edit an Expression Rule

  1. To view the expression rule editor, do one of the following:
    • Double-click the expression rule.
    • From the expression rule's context menu or Action menu, select Open.
    • To view the content of the expression rule, do the following:
      1. From the page toolbar, click View Content to view the expression rule in the content pane.
      2. Click in the preview pane to expand the expression rule editor to the full page.
  2. Click Open Variability to open the Model Version Variability pane.

    Important: Although option groups are listed in the Model Version Variability pane, you cannot use an option group as part of an expression rule. You can only use individual options.

  3. To specify the elements to be included in the expression rule, do one of the following:
    OptionActions
    Enter the expression elements
    1. Click in the editor.
    2. Begin entering the title of the element to populate the list with only those that contain the entered characters.
    3. From the list, select a variant, variant value, option, operator, or statement.
    Select the expression elements Click to the right of the variant, variant value, or option in the Model Version Variability pane to add it to the editor at the insertion point, or at the end of the expression if there is no insertion point.

    Tips:
    • You can open the Model Version Variability pane to see which variants, variant values, and options are available for use in the expression rule.
    • You can filter the variability in the Model Version Variability pane. For more information, see Filtering Listed Items by Title.

  4. From the editor list, select the standard operators and statements to be included in the expression.

    The following standard operators are available:

    • AND
    • NOT
    • OR
    • (
    • )

    The following statements are available:

    • IMPLY
    • EQUIVALENT

    Tip: Expand the sections under Language Information. They show examples of how the variability criteria, standard operators, and the conditional (IMPLY), codependency (EQUIVALENT), and incompatible (IMPLY NOT) statements can be used to build the rule's expression.

  5. Verify the validity of the expression as you build it.

    Note: Any element in the expression that is not valid in that context is displayed in red. Roll over the element for a message that explains why it is not valid. If you select an option group instead of an individual option, the option group is marked as invalid.

  6. To remove a variant, variant value, option, operator, or statement from the expression, select it, then click .
  7. Click Save.

Resolve Conflicts with Other Rules

Any conflict between a cell's status and other rules is immediately indicated by the Conflict with existing rules icon displayed in the right side of the page below the identity card. This means that the expression rule conflicts with a matrix rule or another expression rule already defined for the model version.

  1. Click Conflict with existing rules.
  2. To navigate to the conflicting rule, do one of the following:
    ContextActions
    List Conflict Rules pane Double-click the tile of the conflicting rule.
    List Conflict Rules pane From the context menu of the conflicting rule, select Open.
    Browser toolbar Click Back in the browser to return to the Rules tab, then select the conflicting rule.
    Page breadcrumbs Click a link in the breadcrumbs at the top of the page.

    Note: If you have unsaved changes in the current expression rule, you are prompted to save them before navigating to the conflicting rule.

  3. Update the rule to remove the conflict with the rule you navigated from.
  4. Save the changes you made to resolve the conflict.
  5. Navigate back to the rule that you were defining by clicking Back in the browser or using the app's breadcrumbs at the top of the page.
  6. Click Save.