IRB(1) UNIX IRB(1)NAME
irb - Interactive Ruby Shell
SYNOPSIS
irb [--version] [-dfm] [-I directory] [-r library] [--[no]inspect]
[--[no]readline] [--prompt mode] [--prompt-mode mode] [--inf-ruby-mode]
[--simple-prompt] [--noprompt] [--tracer] [--back-trace-limit n]
[--irb_debug n] [--] [program_file] [argument ...]
DESCRIPTION
irb is the REPL(read-eval&print loop) environment for Ruby programs.
OPTIONS--version
Prints the version of .
-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 encod‐
ings ("Encoding.default_internal") to UTF-8.
-d Same as `ruby -d' . Sets $DEBUG to true.
-f Suppresses read of ~/.irbrc.
-h
--help Prints a summary of the options.
-m Bc mode (load mathn, fraction or matrix are available)
-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
--readline
Uses Readline extension module.
--noreadline
Doesn't use Readline extension module.
--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
--readline.
--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_debug n
Sets internal debug level to n (not for popular use)
ENVIRONMENT
IRBRC
Also irb depends on same variables as ruby(1).
FILES
~/.irbrc
Personal irb initialization.
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
=> nil
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 ALSOruby(1).
REPORTING BUGS
· Security vulnerabilities should be reported via an email to
<security@ruby-lang.org>. Reported problems will be published
after fixed.
· You can report other bugs and feature requests via the Ruby
Issue Tracking System (http://redmine.ruby-lang.org). Do not
report security vulnerabilities via the system because it pub‐
lishes the vulnerabilities immediately.
AUTHORS
Written by Keiju ISHITSUKA.
October 25, 2008 Ruby Programmers Reference Guide IRB(1)
