1IRB(1)                 Ruby Programmer's Reference Guide                IRB(1)
2

NAME

4     irb — Interactive Ruby Shell
5

SYNOPSIS

7     irb [--version] [-dfUw] [-I directory] [-r library]
8         [-E external[:internal]] [-W[level]] [--[no]inspect]
9         [--[no]multiline] [--[no]singleline] [--[no]echo] [--[no]colorize]
10         [--[no]verbose] [--prompt mode] [--prompt-mode mode]
11         [--inf-ruby-mode] [--simple-prompt] [--noprompt] [--tracer]
12         [--back-trace-limit n] [--] [program_file] [argument ...]
13

DESCRIPTION

15     irb is the REPL(read-eval-print loop) environment for Ruby programs.
16

OPTIONS

18     --version      Prints the version of irb.
19
20     -E external[:internal]
21     --encoding external[:internal]
22                    Same as `ruby -E' .  Specifies the default value(s) for
23                    external encodings and internal encoding. Values should be
24                    separated with colon (:).
25
26                    You can omit the one for internal encodings, then the
27                    value (Encoding.default_internal) will be nil.
28
29     -I path        Same as `ruby -I' .  Specifies $LOAD_PATH directory
30
31     -U             Same as `ruby -U' .  Sets the default value for internal
32                    encodings (Encoding.default_internal) to UTF-8.
33
34     -d             Same as `ruby -d' .  Sets $DEBUG to true.
35
36     -f             Suppresses read of ~/.irbrc.
37
38     -w             Same as `ruby -w' .
39
40     -W             Same as `ruby -W' .
41
42     -h
43     --help         Prints a summary of the options.
44
45     -r library     Same as `ruby -r'.  Causes irb to load the library using
46                    require.
47
48     --inspect      Uses `inspect' for output (default except for bc mode)
49
50     --noinspect    Doesn't use inspect for output
51
52     --multiline    Uses multiline editor module.
53
54     --nomultiline  Doesn't use multiline editor module.
55
56     --singleline   Uses singleline editor module.
57
58     --nosingleline
59                    Doesn't use singleline editor module.
60
61     --echo         Show result(default).
62
63     --noecho       Don't show result.
64
65     --colorize     Use colorization.
66
67     --nocolorize   Don't use colorization.
68
69     --verbose      Show details.
70
71     --noverbose    Don't show details.
72
73     --prompt mode
74     --prompt-mode mode
75                    Switch prompt mode. Pre-defined prompt modes are
76                    `default', `simple', `xmp' and `inf-ruby'.
77
78     --inf-ruby-mode
79                    Uses prompt appropriate for inf-ruby-mode on emacs.  Sup‐
80                    presses --multiline and --singleline.
81
82     --simple-prompt
83                    Makes prompts simple.
84
85     --noprompt     No prompt mode.
86
87     --tracer       Displays trace for each execution of commands.
88
89     --back-trace-limit n
90                    Displays backtrace top n and tail n.  The default value is
91                    16.
92

ENVIRONMENT

94     IRBRC
95
96     Also irb depends on same variables as ruby(1).
97

FILES

99     ~/.irbrc                          Personal irb initialization.
100

EXAMPLES

102           % irb
103           irb(main):001:0> 1 + 1
104           2
105           irb(main):002:0> def t(x)
106           irb(main):003:1> x + 1
107           irb(main):004:1> end
108           => :t
109           irb(main):005:0> t(3)
110           => 4
111           irb(main):006:0> if t(3) == 4
112           irb(main):007:1> p :ok
113           irb(main):008:1> end
114           :ok
115           => :ok
116           irb(main):009:0> quit
117           %
118

SEE ALSO

120     ruby(1).
121

REPORTING BUGS

123     ·   Security vulnerabilities should be reported via an email to
124         security@ruby-lang.org.  Reported problems will be published after
125         being fixed.
126
127     ·   Other bugs and feature requests can be reported via the Ruby Issue
128         Tracking System (https://bugs.ruby-lang.org/).  Do not report secu‐
129         rity vulnerabilities via this system because it publishes the vulner‐
130         abilities immediately.
131

AUTHORS

133     Written by Keiju ISHITSUKA.
134
135UNIX                            August 11, 2019                           UNIX
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