Data Management Capabilities > Managing Part Structures > Developing Advanced Selection Logic for Configurable Modules > Basic Steps for Defining Advanced Selection > Adding a Constraint > Expression Editor
  
Expression Editor
The Expression Editor allows you to create a logical expression constraint for a configurable module. An expression evaluates whether one or more conditions are met.
A logical expression can consist of one or multiple parts. You can type your expression directly into the Expression box, or you can use the editor's options to form the expression. The expression is validated when you click Apply.
The Expression Editor provides the following options:
Name
Description
Logical
Allows up to two logical conditions being selected. The available operators are as follows:
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You can select either && or ||, they cannot be used together. ! is always enabled.
• && -- Specifies an AND condition. Both conditions must be met when this operator is used. For example, A>=0 && B>=0. In this example both A and B must be greater or equal to zero for the expression to be valid.
• || -- Specifies an OR condition. Only part of the condition needs to be met when this operator is used. For example, A>=0 || B>=0. In this example either A or B must be greater than equal to zero for the expression to be valid.
• ! -- Specifies a false condition. Indicates the specified parameter or method does not yield the specified value.
Parameter
Tree displays the parameters which are selectable for the configurable module. Only those configurable modules for which a Reference ID is defined are displayed.
Method
If the check box is selected, a corresponding method can be selected. Only methods available for the selected parameter are displayed. If no methods are available, the box is empty.
Operator
If the check box is selected, an operator can be selected. The possible operators are:
• < — Value of parameter is less than what is specified.
• <= — Value of parameter is less than or equal to what is specified.
• == — Value of parameter is equal to the value specified.
• != — Value of parameter is not equal to the parameter specified.
Parameter/Value
Designates a specific value or specifies a parameter to use in the expression. Only those configurable modules for which a Reference ID is defined are displayed.
1. Click Add to add your selections to the existing expression text.
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The expression is not validated until you click Apply.
2. Click Insert () to place parenthesis around the expression displayed in the Expression field.
3. When you have finished creating your expression, click Apply to apply the expression. The expression is validated, and you are informed of any syntax errors.
For more information on the use of logic within an expression, see Using Numeric Operators and Functions in Advanced Logic.