IRB(1)

🎀 IRB(1) — Ruby Programmer's Reference Guide 🎀

✨ NAME ✨

okay so the name is irb and it's basically the Interactive Ruby Shell 💖 It's a REPL (read-eval-print loop), so you type Ruby and it reads, runs, and prints the result right back at you. iconic 💅

👑 SYNOPSIS 👑

irb [--version] [-dfUw] [-I directory] [-r library]
    [-E external[:internal]] [-W[level]] [--[no]inspect]
    [--[no]multiline] [--[no]singleline] [--[no]echo] [--[no]colorize]
    [--[no]autocomplete] [--[no]verbose] [--prompt mode]
    [--prompt-mode mode] [--inf-ruby-mode] [--simple-prompt]
    [--noprompt] [--tracer] [--back-trace-limit n] [--] [program_file]
    [argument ...]

🦋 DESCRIPTION 🦋

so irb is the REPL (read-eval-print loop) environment for Ruby programs. literally where you go to play with Ruby without making a whole file 🧚

🌸 OPTIONS 🌸

• --version — shows you the version of irb 🏷️
• -E external[:internal], --encoding external[:internal] — same as ruby -E. This sets the default external and internal encodings. Separate the two with a colon (:) ✨

you can leave off the internal part, and then Encoding.default_internal just ends up as nil 🙈

• -I path — same as ruby -I. Adds a directory to $LOAD_PATH 📂
• -U — same as ruby -U. Sets the default internal encoding (Encoding.default_internal) to UTF-8 💜
• -d — same as ruby -d. Sets $DEBUG to true 🐛
• -f — skips reading ~/.irbrc 🙅‍♀️
• -w — same as ruby -w ⚠️
• -W — same as ruby -W 🔥
• -h, --help — prints a summary of the options 📝
• -r library — same as ruby -r. Makes irb load the library using require 🎁
• --inspect — uses inspect for output. This is the default, except in bc mode 🔍
• --noinspect — doesn't use inspect for output 🙃
• --multiline — uses the multiline editor module 📜
• --nomultiline — doesn't use the multiline editor module 🚫
• --singleline — uses the singleline editor module 📏
• --nosingleline — doesn't use the singleline editor module 🙅‍♀️
• --extra-doc-dir — adds an extra doc dir for the doc dialog 📚
• --echo — shows the result (this is the default) 👀
• --noecho — hides the result 🫥
• --echo-on-assignment — shows the result on assignment 💅
• --noecho-on-assignment — hides the result on assignment 🙈
• --truncate-echo-on-assignment — shows a truncated result on assignment (default) ✂️
• --colorize — turns on colorization 🌈
• --nocolorize — turns colorization off 🩶
• --autocomplete — turns on autocompletion 🪄
• --noautocomplete — turns autocompletion off 🙅‍♀️
• --regexp-completor — uses regexp based completion 🧵
• --type-completor — uses type based completion 🧠
• --verbose — shows details 🔎
• --noverbose — hides the details 🤫
• --prompt mode, --prompt-mode mode — switches the prompt mode. The pre-defined ones are default, simple, xmp and inf-ruby 💬
• --inf-ruby-mode — uses a prompt that fits inf-ruby-mode on emacs. This one suppresses --multiline and --singleline 🫶

heads up: --inf-ruby-mode turns off --multiline and --singleline for you, so don't expect them to stick around.

• --simple-prompt — makes the prompts simple 🍓
• --noprompt — no prompt mode, so no prompt at all 🫠
• --tracer — displays a trace for each command that runs 🕵️‍♀️
• --back-trace-limit n — displays the top n and the tail n of the backtrace. The default is 16 🧚

🌈 ENVIRONMENT 🌈

• IRB_LANG — the locale irb uses 🗺️
• IRBRC — the path to your personal initialization file 🗝️
• XDG_CONFIG_HOME — irb respects this one! If it's set, irb loads $XDG_CONFIG_HOME/irb/irbrc as your personal initialization file 🏠

irb also depends on the same variables that ruby(1) does, so keep that in mind 💜

🍓 FILES 🍓

• ~/.irbrc — your personal irb initialization file. If IRBRC is set, irb reads $IRBRC instead. If IRBRC isn't set but XDG_CONFIG_HOME is, then $XDG_CONFIG_HOME/irb/irbrc gets loaded 📁

🎀 EXAMPLES 🎀

okay here's a little session so you can see the vibe 👀

% irb
irb(main):001:0> 1 + 1
2
irb(main):002:0> def t(x)
irb(main):003:1> x + 1
irb(main):004:1> end
=> :t
irb(main):005:0> t(3)
=> 4
irb(main):006:0> if t(3) == 4
irb(main):007:1> p :ok
irb(main):008:1> end
:ok
=> :ok
irb(main):009:0> quit
%

🔗 SEE ALSO 🔗

• ruby(1). go read that one too, it's the sister page 👯‍♀️

🚨 REPORTING BUGS 🚨

• Security vulnerabilities should be emailed to security@ruby-lang.org. The problems get published once they're fixed 🔐
• Other bugs and feature requests can go to the Ruby Issue Tracking System (https://bugs.ruby-lang.org/). Please don't report security vulnerabilities there though, because that system publishes them immediately 🙅‍♀️💀

👑 AUTHORS 👑

written by Keiju ISHITSUKA. ICONIC 🫡

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ok bestie that's the whole page 💖 it came from UNIX, dated August 11, 2019, and it's all about IRB(1) 🦋 stay curious, stay caffeinated, and never let a REPL go unexplored ✨🫶