IRB



IRB

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
ENVIRONMENT
FILES
EXAMPLES
SEE ALSO
REPORTING BUGS
AUTHORS

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 encodings ("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> tabs(1)
=> 4
irb(main):006:0> if tabs(1) == 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.







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