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IRB(1)() (ruby programmers reference guide) 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

Prints the version of irb.

external[:internal]
 
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.

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

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

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

Suppresses read of ~/.irbrc.

 
Prints a summary of the options.

Bc mode (load mathn, fraction or matrix are available)

library
Same as `ruby -r'. Causes irb to load the library using require.

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

Doesn't use inspect for output

Uses Readline extension module.

Doesn't use Readline extension module.

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

Uses prompt appropriate for inf-ruby-mode on emacs. Suppresses --readline.

Makes prompts simple.

No prompt mode.

Displays trace for each execution of commands.

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

n
Sets internal debug level to n (not for popular use)

ENVIRONMENT

 

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 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.

And you can report other bugs and feature requests via the Ruby Issue Tracking System (http://bugs.ruby-lang.org). Do not report security vulnerabilities via the system because it publishes the vulnerabilities immediately.

AUTHORS

Written by Keiju ISHITSUKA.

November 7, 2012 UNIX