Decrement

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The decrement command decreases a variable's value by one.

Syntax

decrement(var vA);
--vA;
vA--;
vA = vA - 1;
vA -= 1;

Remarks

Unlike the subn command, the decrement command does not wrap around. If the value of vA is already 0, executing the decrement command has no effect; the value will remain at 0.

When using the alternate syntax vA = vA - 1; WinAGI will compile a decrement command. If you specifically want to use the subn command, you must use the full command syntax (subn(vA, 1);).

Possible Errors

None.

Example

Code:
v50 = 1;
decrement(v50); [ v50 now equals 0
--v50;          [ v50 still equals 0
v50 = v50 - 1;  [ WinAGI compiles this as a decrement command so v50 still equals 0
subn(v50,1);    [ now v50 equals 255

Technical Information

Required Interpreter Version: Available in all AGI versions.
Byte-Code Value: 2 (0x02 hex)

See Also

increment
subn