[RBG7-L] - Variable question

[Jan Johansen]

What syntax can I use to create a variable if I check for the existance of a
variable?

I'm trying to pass parameters that may not exist. So if they dont exist
create them.

I've tried

IF vd1 EXISTS THEN
    SET VAR vd1txt = (CTXT(.vd1))
  ELSE
    SET VAR vd1txt = NULL
ENDIF

but since vd1 doesn't exist it errors out. Turning off error messages
doesn't help.

So is there a way to create a variable based on the fact that another
variable exists or not?

Jan