AW: Constants (was: *varsize array as procedure parameter)

Hi David,

>>If a const is just a pointer to a variable that isn't allowed to be
>>changed ... is there any reason I couldn't take the address of that
>>pointer, assign it to another (non-const) variable, and change the
>>const's value that way?

May be we should explain what happens if a parameter is passed by constant
reference:
If the passed parameter has the same data type and length as required in the
prototype, the address of this parameter field is passed to the called
procedure.
If the passed parameter has a compatible data type or different length, a
temporary field with the required definition is created and initialized with
the parameter value. After the address of this temporary field is passed to
the called procedure.
Because it cannot be determined whether the received address is from the
original field or a temporary field, and to avoid to change some values by
mistake, it's forbidden to change a parameter field that is passed by
constant reference.
The compilers already check it.

Birgitta

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