What if Go support Just In Time compile?

Go’s type reflection is useful in most cases, but when we try to parse some xml or json data to Go inner datas, generate some Go code and compile them in run time will be a better way.

With python’s JIT capability, we can use json file to chang Sublime’s Menus, if we give Go JIT capability, we can change any widgets in a window written with Go at run time with json or xml file.

Is there a way to implement a low level JIT compiler for Go?
How much will it cost?