Where Modules Live

2012.11.15

Ruby modules have been on my mind frequently of late. While exploring the Ruby class hierarchy in irb, I began to wonder where Ruby stores all its built-in and loaded modules.

After lots of fruitless digging around, I finally found them! All modules exist as constants defined on Object. Calling Object.constants will reveal all built-in modules, all loaded modules, and of course other constants defined on Object.

This is probably common knowledge among Ruby ninjas, but it was a great source of excitment for me to find them all the same.