A The One Ruby Reference

This glossary should be used as a quick reference for Ruby; for more depth, click through to the “Full Explanation”s.

How to interpret this reference

This reference is (with a few exceptions) organized by Ruby Class, e.g. String, Array, Hash, etc. Click the firstdraft icon in the top-left corner of the page to slide out the table of contents, scan it, and find a section that interests you. Usually, each section describes a Ruby method. For example, here’s what the section String#split looks like:

• String#split => Array is called the method signature:
  • String since the method is defined for that class.
  • # since it is an instance method (as opposed to a class method, in which case the notation would be .).
  • => Array since the return value of this method is an instance of the class Array.
• Then a description of the method.
• Then examples.
• Then, usually, a link to the longer explanation from the original chapter where the method was first introduced.

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