ByRef and ByVal in VBScript

Question

I\'m facing something weird in VBScript. When writing a procedure where I want the parameter to be passed by reference, the way of calling this procedure changes the way the

Answer 1

IncrementByRef Num

calls and increments using a reference to Num

IncrementByRef (47 + 3)

calls and increments using a reference to "50". Which is discarded on exit.

IncrementByRef (Num)
IncrementByRef (Num + 18)*5
IncrementByRef Cint("32")

Are all legal in BASIC, as they were in FORTRAN. Notoriously, in one early FORTRAN, passing by ref allowed you to change the value of expressions like

5

Which was sufficiently confusing that only very small, early FORTRAN compilers had that kind of behaviour.