TODO

* checker right now only works for fields, not methods
* checker only works if function being checked is on the first line of the program
* checker only works if a single method is being called. Chokes on serial composition (and perhaps other constructs like return statements?)
* checker could print out line where check fails?

* extractor probably only works if prototype modification happends on the top level (probably fine?)
* extractor will do some odd stuff if we modify the "this" prototype (should we just special case not adding anything for this?)


* oddness going on with newlines...seems to work fine with the js scripts read in from testfiles but not if \n is put in a string literal (the is probably just a haskell oddness, don't need to solve)