Ruby Standard Library

The Ruby Standard Library is a large collection of classes and modules you can require in your code to gain additional features.

Below is an overview of the libraries and extensions, followed by a brief description of each.

Libraries

• MakeMakefile: A module used to generate a Makefile for C extensions
• RbConfig: Information about your Ruby configuration and build
• Gem: A package management framework for Ruby

Extensions

• Coverage: Provides coverage measurement for Ruby
• Monitor: Provides a reentrant mutex
• objspace: Extends the ObjectSpace module to add methods for internal statistics
• PTY: Creates and manages pseudo-terminals
• Ripper: Provides an interface for parsing Ruby programs into S-expressions
• Socket: Accesses underlying OS socket implementations

Default gems

• Default gems are shipped with Ruby releases and also available as rubygems.
• Default gems are not uninstallable from the Ruby installation.
• Default gems can be updated using rubygems.
  • e.g. gem update json
• Default gems can be used with bundler environments like unbundled_env.
• Default gems can be used at any version in a Gemfile.
  • e.g. gem "json", ">= 2.6"

Libraries

• Benchmark (GitHub): Provides methods to measure and report the time used to execute code
• Bundler (GitHub): Manage your Ruby application's gem dependencies
• CGI (GitHub): Support for the Common Gateway Interface protocol
• Delegator (GitHub): Provides three abilities to delegate method calls to an object
• DidYouMean (GitHub): "Did you mean?" experience in Ruby
• English (GitHub): Provides references to special global variables with less cryptic names
• ERB (GitHub): An easy-to-use but powerful templating system for Ruby
• ErrorHighlight (GitHub): Highlight error locations in your code
• FileUtils (GitHub): Several file utility methods for copying, moving, removing, etc.
• Find (GitHub): This module supports top-down traversal of a set of file paths
• Forwardable (GitHub): Provides delegation of specified methods to a designated object
• IPAddr (GitHub): Provides methods to manipulate IPv4 and IPv6 IP addresses
• OptionParser (GitHub): Ruby-oriented class for command-line option analysis
• Logger (GitHub): Provides a simple logging utility for outputting messages
• Net::HTTP (GitHub): HTTP client API for Ruby
• Open3 (GitHub): Provides access to stdin, stdout, and stderr when running other programs
• OpenStruct (GitHub): A class to build custom data structures, similar to a Hash
• OpenURI (GitHub): An easy-to-use wrapper for URI::HTTP, URI::HTTPS, and URI::FTP
• PP (GitHub): Provides a PrettyPrinter for Ruby objects
• PrettyPrint (GitHub): Implements a pretty printing algorithm for readable structure
• Prism (GitHub): A portable, error-tolerant Ruby parser
• PStore (GitHub): Implements a file-based persistence mechanism based on a Hash
• Readline (GitHub): Wrapper for the Readline extension and Reline
• Reline (GitHub): GNU Readline and Editline in a pure Ruby implementation
• Resolv (GitHub): Thread-aware DNS resolver library in Ruby
• SecureRandom (GitHub): Interface for a secure random number generator
• Set (GitHub): Provides a class to deal with collections of unordered, unique values
• Shellwords (GitHub): Manipulates strings with the word parsing rules of the UNIX Bourne shell
• Singleton (GitHub): Implementation of the Singleton pattern for Ruby
• Tempfile (GitHub): A utility class for managing temporary files
• Time (GitHub): Extends the Time class with methods for parsing and conversion
• Timeout (GitHub): Auto-terminate potentially long-running operations in Ruby
• TSort (GitHub): Topological sorting using Tarjan's algorithm
• UN (GitHub): Utilities to replace common UNIX commands
• URI (GitHub): A Ruby module providing support for Uniform Resource Identifiers
• YAML (GitHub): The Ruby client library for the Psych YAML implementation
• WeakRef (GitHub): Allows a referenced object to be garbage-collected

Extensions

• Date (GitHub): Represents dates, with a subclass for dates with time and timezones
• Digest (GitHub): Provides a framework for message digest libraries
• Etc (GitHub): Provides access to information typically stored in the UNIX /etc directory
• Fcntl (GitHub): Loads constants defined in the OS fcntl.h C header file
• Fiddle (GitHub): A libffi wrapper for Ruby
• IO.console (GitHub): Extensions for the IO class, including IO.console, IO.winsize, etc.
• JSON (GitHub): Implements JavaScript Object Notation for Ruby
• OpenSSL (GitHub): Provides SSL, TLS, and general-purpose cryptography for Ruby
• Pathname (GitHub): Representation of the name of a file or directory on the filesystem
• Psych (GitHub): A YAML parser and emitter for Ruby
• StringIO (GitHub): Pseudo-I/O on String objects
• StringScanner (GitHub): Provides lexical scanning operations on a String
• TmpDir (GitHub): Extends the Dir class to manage the OS temporary file path
• WIN32OLE (GitHub): Provides an interface for OLE Automation in Ruby
• Zlib (GitHub): Ruby interface for the zlib compression/decompression library

Tools

• IRB (GitHub): Interactive Ruby command-line tool for REPL (Read Eval Print Loop)
• RDoc (GitHub): Documentation generator for Ruby

Bundled gems

• Bundled gems are shipped with Ruby releases and also available as rubygems.
  • They are only bundled with Ruby releases.
  • They can be uninstalled from the Ruby installation.
  • They need to be declared in a Gemfile when used with bundler.

Libraries

• minitest: A test library supporting TDD, BDD, mocking, and benchmarking
• power_assert: Power Assert for Ruby
• rake: Ruby build program with capabilities similar to make
• test-unit: A compatibility layer for MiniTest
• rexml: An XML toolkit for Ruby
• rss: A family of libraries supporting various XML-based "feeds"
• net-ftp: Support for the File Transfer Protocol
• net-imap: Ruby client API for the Internet Message Access Protocol
• net-pop: Ruby client library for POP3
• net-smtp: Simple Mail Transfer Protocol client library for Ruby
• matrix: Represents a mathematical matrix
• prime: Prime numbers and factorization library
• rbs: RBS is a language to describe the structure of Ruby programs
• typeprof: A type analysis tool for Ruby code based on abstract interpretation
• debug: Debugging functionality for Ruby
• racc: A LALR(1) parser generator written in Ruby
• mutex_m: Mixin to extend objects to be handled like a Mutex
• getoptlong: Parse command line options similar to the GNU C getopt_long()
• base64: Support for encoding and decoding binary data using a Base64 representation
• bigdecimal: Provides arbitrary-precision floating point decimal arithmetic
• observer: Provides a mechanism for the publish/subscribe pattern in Ruby
• abbrev: Calculates a set of unique abbreviations for a given set of strings
• resolv-replace: Replace Socket DNS with Resolv
• rinda: The Linda distributed computing paradigm in Ruby
• drb: Distributed object system for Ruby
• nkf: Ruby extension for the Network Kanji Filter
• syslog: Ruby interface for the POSIX system logging facility
• csv: Provides an interface to read and write CSV files and data