Late Evaluation of Variables in Expressions

The functions VVALUE, VLOGICAL, and VTEXT are used for late evaluation of PML variables, that is, they enable you to specify PML variables in expressions which will not be evaluated until the expression is evaluated.

For example, when you are creating a report template, you are actually creating a macro which will run when a report is generated. All variables in a report template must therefore be preceded by a suitable late evaluation operator. Otherwise, the system will try to substitute a value for the variable when it is entered on the form.

The difference between the operators is the type of output. VVALUE is used to output a numeric value, VLOGICAL to output a logical variable and VTEXT to output a text variable.