irb - Man Page

• Start the interactive shell: irb

tldr.sh

irb is the REPL(read-eval-print loop) environment for Ruby programs.

--version

Prints the version of irb.

-E external[:internal]

--encoding external[:internal]

Same as `ruby -E' . Specifies the default value(s) for external encodings and internal encoding. Values should be separated with colon (:).

You can omit the one for internal encodings, then the value (Encoding.default_internal) will be nil.

-I path

Same as `ruby -I' . Specifies $LOAD_PATH directory

-U

Same as `ruby -U' . Sets the default value for internal encodings (Encoding.default_internal) to UTF-8.

-d

Same as `ruby -d' . Sets $DEBUG to true.

-f

Suppresses read of ~/.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'. Causes irb to load the library using require.

--inspect

Uses `inspect' for output (default except for bc mode)

--noinspect

Doesn't use inspect for output

--multiline

Uses multiline editor module.

--nomultiline

Doesn't use multiline editor module.

--singleline

Uses singleline editor module.

--nosingleline

Doesn't use singleline editor module.

--extra-doc-dir

Add an extra doc dir for the doc dialog.

--echo

Show result (default).

--noecho

Don't show result.

--echo-on-assignment

Show result on assignment.

--noecho-on-assignment

Don't show result on assignment.

--truncate-echo-on-assignment

Show truncated result on assignment (default).

--colorize

Use colorization.

--nocolorize

Don't use colorization.

--autocomplete

Use autocompletion.

--noautocomplete

Don't use autocompletion.

--regexp-completor

Use regexp based completion.

--type-completor

Use type based completion.

--verbose

Show details.

--noverbose

Don't show details.

--prompt mode

--prompt-mode mode

Switch prompt mode. Pre-defined prompt modes are `default', `simple', `xmp' and `inf-ruby'.

--inf-ruby-mode

Uses prompt appropriate for inf-ruby-mode on emacs. Suppresses --multiline and --singleline.

--simple-prompt

Makes prompts simple.

--noprompt

No prompt mode.

--tracer

Displays trace for each execution of commands.

--back-trace-limit n

Displays backtrace top n and tail n. The default value is 16.

IRB_LANG

The locale used for irb.

IRBRC

The path to the personal initialization file.

XDG_CONFIG_HOME

irb respects XDG_CONFIG_HOME. If this is set, load $XDG_CONFIG_HOME/irb/irbrc as a personal initialization file.

Also irb depends on same variables as ruby(1).

~/.irbrc

Personal irb initialization. If IRBRC is set, read $IRBRC instead. If IRBRC is not set and XDG_CONFIG_HOME is set, $XDG_CONFIG_HOME/irb/irbrc is loaded.

% 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

%

ruby(1).

• Security vulnerabilities should be reported via an email to security@ruby-lang.org. Reported problems will be published after being fixed.

• Other bugs and feature requests can be reported via the Ruby Issue Tracking System (https://bugs.ruby-lang.org/). Do not report security vulnerabilities via this system because it publishes the vulnerabilities immediately.

Written by Keiju ISHITSUKA.