Getting started

Overview

Installing Ruby

Ruby editors

Notation conventions

Interactive Ruby

Mailing List FAQ

Basic Ruby

Hello world

Strings

Alternate quotes

Here documents

ASCII

Encoding

Introduction to objects

Ruby basics

Data types — numbers, strings, hashes and arrays

Writing methods

Classes and objects

Exceptions

Ruby Semantic reference

• Syntax
  • Lexicology
    • Identifiers
    • Comments
    • Embedded Documentation
    • Reserved Words
    • Expressions
  • Variables and Constants
    • Local Variables
    • Instance Variables
    • Class Variables
    • Global Variables
    • Constants
    • Pseudo Variables
    • Pre-defined Variables
  • Literals
    • Numerics
    • Strings
      • Interpolation
      • Backslash Notation
      • The % Notation
    • Command Expansion
    • Regular Expressions
    • Arrays
    • Hashes
    • Ranges
    • Symbols
  • Operators
    • Assignment
      • Self Assignment
      • Multiple Assignment
      • Conditional Assignment
    • Scope
    • and
    • or
    • not
  • Control Structures
    • Conditional Branches
      • if
        • if modifier
      • unless
        • unless modifier
      • case
    • Loops
      • while
        • while modifier
      • until
        • until modifier
      • for
        • for ... in
      • break
      • redo
      • next
      • retry
    • Exception Handling
      • raise
      • begin
        • rescue modifier
    • Miscellanea
      • return
      • returning
  • Methods
    • super
    • Iterators
    • yield
  • Classes
    • Class Definition
      • Instance Variables
      • Class Variables
      • Class Methods
      • Instantiation
    • Declaring Visibility
      • Private
      • Public
      • Protected
      • Instance Variables
    • Inheritance
    • Mixing in Modules
    • Ruby Class Meta-Model
    • Ruby Hooks add the ability to know when new methods are defined et al.

See also some rdoc documentation on the various keywords.

Built in Classes

This is a list of classes that are available to you by default in Ruby. They are pre-defined in “core.”

• Built-in Functions
• Predefined Variables (globals)
• Predefined Classes
  • Object
    • Array
    • Class
    • Comparable
    • Encoding
    • Enumerable
      • Enumerable::Enumerator
    • Enumerator
    • Exception
    • FalseClass
    • Fiber
    • IO
      • File
        • File::Stat
      • GC
        • GC::Profiler
    • Marshal
    • Method
    • Math
    • Module
      • Class
    • NilClass
    • Numeric
      • Integer
        • Bignum
        • Fixnum
      • Float
    • Range
    • Regexp
    • RubyVM
    • String
    • Struct
      • Struct::Tms
    • Symbol
    • Time
    • Thread
    • TrueClass

Available Standard Library Modules

These are parts of Ruby that you have available (in the standard library, or via installation as a gem). To use them you typically have to require some filename, for example require 'tracer' would make accessible to you the Tracer class.

You can see a list of basically all the (std lib ruby) modules available in the ruby source and lib readme. There are a several more modules available in the std lib, which are C based extensions. You can see their list here.

• BigDecimal gives you a way to have arbitrary precision Decimal style numbers. Never succumb to rounding errors again!
• Debugger gives you a way to step through debug your Ruby code.
• Distributed Ruby (DRb) gives you a way to make remote procedure calls against objects in a different VM.
• mkmf is a utility used to generate makefiles for ruby extensions.
• Mutex gives you a way to control thread concurrency.
• Net::HTTP gives you a way to download web pages.
• Open3 gives you a way to run a sub-process and have easy access to its I/O.
• OpenSSL is a wrapper to the OpenSSL (C) library, giving you access to secure socket connections.
• Pathname gives you an easy way to manipulate filenames and create/remove files.
• Profiler gives you a way to profile what is taking up the most time in your code.
• OpenURI gives you a way to download files using ruby.
• REXML is a way to parse XML in pure Ruby.
• Ripper gives you a way to parse pure Ruby code into an AST.
• Socket gives you access to Network connectivity.
• Tracer gives you a way to see which lines of your code are being executed and in what order.
• Win32::Registry gives you a way to query and edit the windows registry.
• Win32API gives you a way to call into specific windows core methods easily.
• WIN32OLE gives you a way to use Windows OLE.

Other Libraries

• Database Interface Modules

Documentation

Learning Ruby

• Try Ruby - learn the basics of the Ruby language in your browser.
• LearnStreet - Free online Ruby tutorials & practice exercises
• A Ruby Tutorial that Anyone can Edit (broken)
• Learning Ruby A free tool to find and learn Ruby concepts

Books