"/:" syntax and AS3 queston

programming flash
1

I have inherited an old project and want to update it to AS3, but I am confused by the usage of some of the syntax. Here is the section of code I am referring to:

 
speed = 125;
drag = "/dragControl";
/:w = getProperty("/nav", _width);
/:xPos = getProperty(drag, _x);
/:yPos = getProperty(drag, _y);
/:xPos = eval("/:xPos") - 400;
setProperty("/nav", _x, getProperty("/nav", _x) - eval("/:xPos") / speed);
if (Number(getProperty("/nav", _x)) < Number(-eval("/:w") / 2))
{
    setProperty("/nav", _x, 1.000000E-002);
}
else if (Number(getProperty("/nav", _x)) > 0)
{
    setProperty("/nav", _x, -eval("/:w") / 2);
}

I am unfamiliar with the “/:” syntax and what it would take to update this to AS3. Any help would be greatly appreciated.