Data Management Capabilities > Managing Configurable Products > Windchill Options and Variants Capabilities > Assigning Expressions > Defining Advanced Expressions > Syntax for Creating Advanced Expressions
  
Syntax for Creating Advanced Expressions
An advanced expression consists of the following elements:
Logical operators:
“+” or “&&” – as AND
“/” or “||” – as OR
“-” or “!” – as NOT
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Logical operators can be configured to map to the site-specific operators by changing the properties file. For details, see Configuring Expressions.
Parenthesis for grouping logic: “(“ and “)”
Expression members (choices)
Spaces and <new line> for readability
Following is an example of an expression:
(Red && Small) || (Blue && !Large) – This expression specifies that the part is included in the product structure if Red and Small are requested, or if Blue and not Large are requested.
Consider these guidelines for creating expressions:
Choice names must be globally unique.
An expression can use a combination of choices from the assigned option set.
When including a choice, do not include the option name.
If a choice name starts with a number or the name contains a space or a special character, include the name in quotes. For example, you can have an expression: “light blue” + “64GB” + “-48” / ”+48”
Your organization can customize the assignment of expressions to specify a particular format for defining expression or to perform site-specific validation of expressions. For more information, see Configuring Expressions.