Interactive Ruby Shell

Interactive Ruby Shell

Screenshot The screenshot session as same as the article example
Developer(s)	Keiju Ishitsuka
Stable release	1.2.4 / May 2, 2020 (2020-05-02)[1]
Repository	github.com/ruby/irb
Written in	Ruby
Operating system	Cross-platform
Platform	Ruby interpreter
Type	Ruby shell
License	Ruby License BSD License
Website	www.ruby-lang.org/en/

Interactive Ruby Shell (IRB or irb) is a REPL for programming in the object-oriented scripting language Ruby. The abbreviation irb is a portmanteau of the word "interactive" and the filename extension for Ruby files, ".rb".

The program is launched from a command line and allows the execution of Ruby commands with immediate response, experimenting in real-time. It features command history, line editing capabilities, and job control, and is able to communicate directly as a shell script over the Internet and interact with a live server. It was developed by Keiju Ishitsuka.

Syntax and use

Syntax:

irb [ options ] [ programfile ] [ argument... ] 

Example:

irb(main):001:0> n = 5 => 5 irb(main):002:0> def fact(n) irb(main):003:1>  if n <= 1 irb(main):004:2>  1 irb(main):005:2>  else irb(main):006:2*  n * fact(n - 1) irb(main):007:2>  end irb(main):008:1> end => :fact irb(main):009:0> fact(n) => 120 irb(main):001:0> class Cat irb(main):002:1>  def meow irb(main):003:2>  puts 'Meow!' irb(main):004:2>  end irb(main):005:1> end => :meow irb(main):006:0> Cat.new.meow Meow! 

See also

• Comparison of computer shells

References

External links

• "Code and run Ruby online" A powerful interactive Ruby shell
• "Try Ruby" Online IRB
• "When Trouble Strikes" chapter from Programming Ruby
• "Interactive Ruby Shell" chapter from Programming Ruby