11. One or more computer-readable non-transitory storage media embodying software operable when executed by one or more computer systems to: mark an object in source code of a software program written in an object-oriented scripting language, wherein marking the object is performed with a keyword; mark one or more functions in the source code of the software program; construct a control flow graph (CFG) for the software program; and determine whether there is any path in the CFG that leads from a first node corresponding to the marked object to a second node corresponding to any marked function paired with the object.
14. The media of claim 11 , wherein the marked object is a variable.