Example:
Assume that X is defined as in the "Examples of $Qlength()" earlier in this chapter;
$QLENGTH (X="^|""XXX""|ABC(1,2,3,5,6)")
WRITE $QSUBSCRIPT(X,-2)
GTM>error
WRITE $QSUBSCRIPT(X,-1)
GTM>XXX
WRITE $QSUBSCRIPT(X,0)
GTM>^ABC
WRITE $QSUBSCRIPT(X,1)
GTM>1
WRITE $QSUBSCRIPT(X,4)
GTM>5
WRITE $QSUBSCRIPT(X,7)
GTM>""