[power-pro] could it pass the parameter to the function

[Wai]

hello,

I would like to ask the question about the function.could it pass the parameter 
to the function.For example,
after Running the following script, my expected result is 12, but the real is 0.
What is the wrong.

function calc(a,b)
        v = a*b
        win.debug(v)
quit

@calc(3,4)