If you are referring to the system variable when you have another, same-named identifier in scope, you must include the category name as a qualifier. For example, you must specify ConverseVar.eventKey rather than eventKey if a second variable named eventKey is in scope. If a same-named identifier is not in scope, the qualifier is optional.
Related concepts
References to variables in EGL
Scoping rules and "this" in EGL
Related reference
@DLI
ConverseVar
DLIVar
SysVar
VGVar