Using References to Expressions

References to expressions can be used in decision tables. They can be referenced from table headers and within table body.

• $Expr.C1 is used to reference the expression for condition C1. To address action or return expression use RET1 and A1 respectively.
• $Expr.$C1.param1 is an expression defined as a value in a column for the param1 condition parameter. $C1 is optional. For instance, in the example below, parameter cond is the condition parameter for condition C2. It’s important to use named parameters which is possible in decision tables of Rules type or when working with external conditions, actions, or returns in smart tables.

$Expr.C1, $Expr.$C1.param1 return the expression type that contains following attributes:

• ast - returns AST (Abstract Syntax Tree) tree for the expression
• textValue - returns a string representing an expression

Note: If a cell, which is expected to contain an expression or formula, is empty, it will return null.