function, the evaluator calls the function directly, passing it a pointer to the argument stack and the number of arguments to the function call. The function is responsible for popping off all of the arguments and pushing the return value on the argument stack.</P>
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Special actions have to be taken if an operand or argument is a cell reference. If the cell is an argument to a function, or an operand (and the operator is not a range-separator or range-intersection), the evaluator will call its callback r