irb.1

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IRB(1) Ruby Programmer’s Reference Guide IRB(1)

NAME

irb — Interactive Ruby Shell

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

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

OPTIONS
−-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.

ENVIRONMENT
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).

FILES
~/.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.

EXAMPLES

% 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).

REPORTING BUGS
•

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.

AUTHORS

Written by Keiju ISHITSUKA.

UNIX August 11, 2019 UNIX

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