Programming Ruby 1.9: The Pragmatic Programmers' Guide

This is the reference manual for Ruby, including a description of all the standard library modules, a complete reference to all built-in classes and modules (including all the new and changed methods introduced by Ruby 1.9). It also includes all the new and changed syntax and semantics introduced since Ruby 1.8. Learn about the new parameter passing rules, local variable scoping in blocks, fibers, and the new block declaration syntax, among other exciting new features.