irb − Interactive Ruby Shell
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 ...]
irb is the REPL(read-eval-print loop) environment for Ruby programs.
−-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)
IRBRC |
Also irb depends on same variables as ruby(1). |
~/.irbrc
Personal irb initialization.
% 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
%
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.
Written by Keiju ISHITSUKA.
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.