This file is actually built out.  What you'll want to do is to copy the d3 file this method is located in and patch it. Then update the makefile.   ```src/core/selection-append.js``` as an example of how i cloned off the selection module and replaced it with a modified version.  You'll want to clone ```lib/d3/src/core/transform.js``` and put it into ```src/core/transform.js``` and update it with your changes. Then go into the makefile and replace ```lib/d3/src/core/transform.js``` with the path to your file ```sr/core/transform.js```