The EXPRESSIONOF keyword enables you to express references to objects using complex operators and delimiters. EXPRESSIONOF is usually used with the special argument DATA, which refers to data elements and data structures; like this: EXPRESSIONOF DATA.

This keyword combination provides a text box in which definition values are entered as a series of strings. The division between one definition value and the next is determined by white space. By convention, + (plus sign) is used to divide the individual definition values, but it is not required.