Contents > 8 Defining Custom Design Metrics and Rules > 8.5 Expression Terms > 8.5.3 Set Expressions

8.5.3 Set Expressions

A set expression is an expression that returns a set. It is made up of identifiers (names of sets), and set operations. Identifiers have been described in Section "Identifiers". The admissible set operations are: The dot operator has precedence over the * operator, which has precedence over the + and - operators. A+B-C is equivalent to (A+B)-C, not A+(B-C). Use parenthesis to enforce the intended precedence.

An example for a valid set expression is ((A+B)-context.C)*D.