Parameters are supplied from a Parent to Children via Child Rules.
Think of parameters as inputs supplied to Children by their Parent.
•The Child Design defines what its inputs are (including Parameter rules—see previous topic).
•The Parent Design optionally supplies those inputs via a Child Rule.
When a Child Rule is created in a Design, it specifies the Design to use for the Children.
•For each Parameter Rule in the Child Design, a Parameter is shown as a row in the Parameters grid.
•A rule expression may be optionally supplied to the Child by clicking on a row in the Parameters Grid and entering the expression.
•This supplied expression is evaluated in the context of the parent.
•If an expression is not supplied to a Parameter, the default defined in the Child Design’s Parameter Rule is evaluated in the context of the Child.
Parameter expressions supplied from the World to the root Design are called Top Level Parameters.
