Kathleen Dollard’s CodegendotNet seems to satisfy Generative Programming Generators definition. Generative programming was a book that aimed to set the stage for improvements in productivity. Kathleen Dollard has provided examples to demonstrate how this technology can work. The main problem is that her demo works too well and people are trying to use it as the code generation template.
Here is the overview of codegen as implemneted in an OO-language: here