passing a filehandle to a function

I know in some other laguages I have to explicity declare the type of variable (string, int, float) I'll be passing to a function

In this case I wish to pass a filehandle to a function
eg. in this example "title_screen" is a filehandle

draw (title_screen)
end

;----------------------------------
Function draw (handle)

drawimage handle,0,0

End Function
;----------------------------------

My question is, is this code ok, or in the function do I have to declare handle as being some type of float or long int or something.