misplaced operator or missing operand at 'operator_symbol'
    Facility: DEBUG, VMS Debugger
    Explanation: An operand was encountered in a language expression
    when an operator was expected, or an operand did not follow an
    operator. For example, 'EVALUATE A B' or 'EVALUATE A + ' instead
    of 'EVALUATE A + B'.
    User Action: Specify valid operators between operands.