Working with source maps

Source maps are a great new idea from the web development community. They use a special map file format to trace characters of a served file (such as JavaScript or CSS) back to locations in a corresponding source file. This allows more transparency for automated file transformations such as compiling or minifying. If a file contains a special header or comment pointing to an accompanying .map file, the browser can read this source map to translate between the code it is running and the original source that it should display to the developer.

Note

To read a full description of how source maps are implemented, see the proposed specification at https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit.

To work with source maps, we'll need to make sure that both our CoffeeScript compiler and our browser tools are up-to-date. Since this is a new technology, support for them has only been added recently.

We must use the CoffeeScript compiler from...