Address Symbol '@'

The Symbol Address operator returns the address of the symbol following it. Symbol Address can be used in variable and integer constant expressions, but not in floating-point constant expressions. Example:

BYTE[@Str] := "A"

In the above example, the Symbol Address operator returns the address of the Str symbol, which is then used by the BYTE memory array reference to store the character "A" at that address.

Symbol Address is often used to pass the address of strings and data structures, defined in a DAT block, to methods that operate on them.

It is important to note that this is a special operator that behaves differently in variable expressions than it does in constant expressions. At run time, like our example above shows, it returns the absolute address of the symbol following it. This run-time, absolute address consists of the object's program base address plus the symbol's offset address.

In constant expressions, it only returns the symbol's offset within the object. It cannot return the absolute address, effective at run time, because that address changes depending on the object's actual address at run time. To properly use the Symbol Address in a constant, such as a table of data, see the Object Address Plus Symbol operator, below.