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Module: IRB

Relationships & Source Files
Namespace Children
Modules:
Classes:
Exceptions:
Defined in: lib/irb.rb,
lib/irb/color.rb,
lib/irb/completion.rb,
lib/irb/context.rb,
lib/irb/easter-egg.rb,
lib/irb/extend-command.rb,
lib/irb/frame.rb,
lib/irb/help.rb,
lib/irb/init.rb,
lib/irb/input-method.rb,
lib/irb/inspector.rb,
lib/irb/locale.rb,
lib/irb/magic-file.rb,
lib/irb/notifier.rb,
lib/irb/output-method.rb,
lib/irb/src_encoding.rb,
lib/irb/version.rb,
lib/irb/workspace.rb,
lib/irb/cmd/chws.rb,
lib/irb/cmd/fork.rb,
lib/irb/cmd/help.rb,
lib/irb/cmd/info.rb,
lib/irb/cmd/load.rb,
lib/irb/cmd/nop.rb,
lib/irb/cmd/pushws.rb,
lib/irb/cmd/subirb.rb,
lib/irb/ext/change-ws.rb,
lib/irb/ext/history.rb,
lib/irb/ext/loader.rb,
lib/irb/ext/multi-irb.rb,
lib/irb/ext/save-history.rb,
lib/irb/ext/tracer.rb,
lib/irb/ext/use-loader.rb,
lib/irb/ext/workspaces.rb,
lib/irb/lc/error.rb,
lib/irb/lc/ja/encoding_aliases.rb,
lib/irb/lc/ja/error.rb

Overview

IRB stands for “interactive Ruby” and is a tool to interactively execute Ruby expressions read from the standard input.

The .irb command from your shell will start the interpreter.

Usage

Use of irb is easy if you know Ruby.

When executing irb, prompts are displayed as follows. Then, enter the Ruby expression. An input is executed when it is syntactically complete.

$ irb
irb(main):001:0> 1+2
#=> 3
irb(main):002:0> class Foo
irb(main):003:1>  def foo
irb(main):004:2>    print 1
irb(main):005:2>  end
irb(main):006:1> end
#=> nil

The singleline editor module or multiline editor module can be used with irb. Use of multiline editor is default if it's installed.

Command line options

Usage:  irb.rb [options] [programfile] [arguments]
  -f                Suppress read of ~/.irbrc
  -d                Set $DEBUG to true (same as `ruby -d')
  -r load-module    Same as `ruby -r'
  -I path           Specify $LOAD_PATH directory
  -U                Same as `ruby -U`
  -E enc            Same as `ruby -E`
  -w                Same as `ruby -w`
  -W[level=2]       Same as `ruby -W`
  --inspect         Use `inspect' for output (default except for bc mode)
  --noinspect       Don't use inspect for output
  --multiline       Use multiline editor module
  --nomultiline     Don't use multiline editor module
  --singleline      Use singleline editor module
  --nosingleline    Don't use singleline editor module
  --colorize        Use colorization
  --nocolorize      Don't use colorization
  --prompt prompt-mode
  --prompt-mode prompt-mode
                    Switch prompt mode. Pre-defined prompt modes are
                    `default', `simple', `xmp' and `inf-ruby'
  --inf-ruby-mode   Use prompt appropriate for inf-ruby-mode on emacs.
                    Suppresses --multiline and --singleline.
  --simple-prompt   Simple prompt mode
  --noprompt        No prompt mode
  --tracer          Display trace for each execution of commands.
  --back-trace-limit n
                    Display backtrace top n and tail n. The default
                    value is 16.
  -v, --version     Print the version of irb

Configuration

IRB reads from ~/.irbrc when it's invoked.

If ~/.irbrc doesn't exist, .irb will try to read in the following order:

  • .irbrc

  • irb.rc

  • _irbrc

  • $irbrc

The following are alternatives to the command line options. To use them type as follows in an .irb session:

IRB.conf[:IRB_NAME]="irb"
IRB.conf[:INSPECT_MODE]=nil
IRB.conf[:IRB_RC] = nil
IRB.conf[:BACK_TRACE_LIMIT]=16
IRB.conf[:USE_LOADER] = false
IRB.conf[:USE_MULTILINE] = nil
IRB.conf[:USE_SINGLELINE] = nil
IRB.conf[:USE_COLORIZE] = true
IRB.conf[:USE_TRACER] = false
IRB.conf[:IGNORE_SIGINT] = true
IRB.conf[:IGNORE_EOF] = false
IRB.conf[:PROMPT_MODE] = :DEFAULT
IRB.conf[:PROMPT] = {...}

Auto indentation

To disable auto-indent mode in irb, add the following to your .irbrc:

IRB.conf[:AUTO_INDENT] = false

Autocompletion

To enable autocompletion for irb, add the following to your .irbrc:

require 'irb/completion'

History

By default, irb will store the last 1000 commands you used in IRB.conf[:HISTORY_FILE] (~/.irb_history by default).

If you want to disable history, add the following to your .irbrc:

IRB.conf[:SAVE_HISTORY] = nil

See Context#save_history= for more information.

The history of results of commands evaluated is not stored by default, but can be turned on to be stored with this .irbrc setting:

IRB.conf[:EVAL_HISTORY] = <number>

See Context#eval_history= and History class. The history of command results is not permanently saved in any file.

Customizing the IRB Prompt

In order to customize the prompt, you can change the following Hash:

IRB.conf[:PROMPT]

This example can be used in your .irbrc

IRB.conf[:PROMPT][:MY_PROMPT] = { # name of prompt mode
  :AUTO_INDENT => false,          # disables auto-indent mode
  :PROMPT_I =>  ">> ",		# simple prompt
  :PROMPT_S => nil,		# prompt for continuated strings
  :PROMPT_C => nil,		# prompt for continuated statement
  :RETURN => "    ==>%s\n"	# format to return value
}

IRB.conf[:PROMPT_MODE] = :MY_PROMPT

Or, invoke irb with the above prompt mode by:

irb --prompt my-prompt

Constants PROMPT_I, PROMPT_S and PROMPT_C specify the format. In the prompt specification, some special strings are available:

%N    # command name which is running
%m    # to_s of main object (self)
%M    # inspect of main object (self)
%l    # type of string(", ', /, ]), `]' is inner %w[...]
%NNi  # indent level. NN is digits and means as same as printf("%NNd").
      # It can be omitted
%NNn  # line number.
%%    # %

For instance, the default prompt mode is defined as follows:

IRB.conf[:PROMPT_MODE][:DEFAULT] = {
  :PROMPT_I => "%N(%m):%03n:%i> ",
  :PROMPT_N => "%N(%m):%03n:%i> ",
  :PROMPT_S => "%N(%m):%03n:%i%l ",
  :PROMPT_C => "%N(%m):%03n:%i* ",
  :RETURN => "%s\n" # used to printf
}

irb comes with a number of available modes:

# :NULL:
#   :PROMPT_I:
#   :PROMPT_N:
#   :PROMPT_S:
#   :PROMPT_C:
#   :RETURN: |
#     %s
# :DEFAULT:
#   :PROMPT_I: ! '%N(%m):%03n:%i> '
#   :PROMPT_N: ! '%N(%m):%03n:%i> '
#   :PROMPT_S: ! '%N(%m):%03n:%i%l '
#   :PROMPT_C: ! '%N(%m):%03n:%i* '
#   :RETURN: |
#     => %s
# :CLASSIC:
#   :PROMPT_I: ! '%N(%m):%03n:%i> '
#   :PROMPT_N: ! '%N(%m):%03n:%i> '
#   :PROMPT_S: ! '%N(%m):%03n:%i%l '
#   :PROMPT_C: ! '%N(%m):%03n:%i* '
#   :RETURN: |
#     %s
# :SIMPLE:
#   :PROMPT_I: ! '>> '
#   :PROMPT_N: ! '>> '
#   :PROMPT_S:
#   :PROMPT_C: ! '?> '
#   :RETURN: |
#     => %s
# :INF_RUBY:
#   :PROMPT_I: ! '%N(%m):%03n:%i> '
#   :PROMPT_N:
#   :PROMPT_S:
#   :PROMPT_C:
#   :RETURN: |
#     %s
#   :AUTO_INDENT: true
# :XMP:
#   :PROMPT_I:
#   :PROMPT_N:
#   :PROMPT_S:
#   :PROMPT_C:
#   :RETURN: |2
#         ==>%s

Restrictions

Because irb evaluates input immediately after it is syntactically complete, the results may be slightly different than directly using Ruby.

IRB Sessions

IRB has a special feature, that allows you to manage many sessions at once.

You can create new sessions with Irb.irb, and get a list of current sessions with the jobs command in the prompt.

Commands

JobManager provides commands to handle the current sessions:

jobs    # List of current sessions
fg      # Switches to the session of the given number
kill    # Kills the session with the given number

The exit command, or .irb_exit, will quit the current session and call any exit hooks with .irb_at_exit.

A few commands for loading files within the session are also available:

source

Loads a given file in the current session and displays the source lines, see IrbLoader#source_file

irb_load

Loads the given file similarly to Kernel#load, see IrbLoader#irb_load

irb_require

Loads the given file similarly to Kernel#require

Configuration

The command line options, or .conf, specify the default behavior of Irb.irb.

On the other hand, each conf in IRB@Command+line+options is used to individually configure .irb.

If a proc is set for IRB.conf[:IRB_RC], its will be invoked after execution of that proc with the context of the current session as its argument. Each session can be configured using this mechanism.

Session variables

There are a few variables in every Irb session that can come in handy:

_

The value command executed, as a local variable

__

The history of evaluated commands. Available only if IRB.conf[:EVAL_HISTORY] is not nil (which is the default). See also IRB::Context#eval_history= and IRB::History.

__[line_no]

Returns the evaluation value at the given line number, line_no. If line_no is a negative, the return value line_no many lines before the most recent return value.

Example using IRB Sessions

# invoke a new session
irb(main):001:0> irb
# list open sessions
irb.1(main):001:0> jobs
  #0->irb on main (#<Thread:0x400fb7e4> : stop)
  #1->irb#1 on main (#<Thread:0x40125d64> : running)

# change the active session
irb.1(main):002:0> fg 0
# define class Foo in top-level session
irb(main):002:0> class Foo;end
# invoke a new session with the context of Foo
irb(main):003:0> irb Foo
# define Foo#foo
irb.2(Foo):001:0> def foo
irb.2(Foo):002:1>   print 1
irb.2(Foo):003:1> end

# change the active session
irb.2(Foo):004:0> fg 0
# list open sessions
irb(main):004:0> jobs
  #0->irb on main (#<Thread:0x400fb7e4> : running)
  #1->irb#1 on main (#<Thread:0x40125d64> : stop)
  #2->irb#2 on Foo (#<Thread:0x4011d54c> : stop)
# check if Foo#foo is available
irb(main):005:0> Foo.instance_methods #=> [:foo, ...]

# change the active session
irb(main):006:0> fg 2
# define Foo#bar in the context of Foo
irb.2(Foo):005:0> def bar
irb.2(Foo):006:1>  print "bar"
irb.2(Foo):007:1> end
irb.2(Foo):010:0>  Foo.instance_methods #=> [:bar, :foo, ...]

# change the active session
irb.2(Foo):011:0> fg 0
irb(main):007:0> f = Foo.new  #=> #<Foo:0x4010af3c>
# invoke a new session with the context of f (instance of Foo)
irb(main):008:0> irb f
# list open sessions
irb.3(<Foo:0x4010af3c>):001:0> jobs
  #0->irb on main (#<Thread:0x400fb7e4> : stop)
  #1->irb#1 on main (#<Thread:0x40125d64> : stop)
  #2->irb#2 on Foo (#<Thread:0x4011d54c> : stop)
  #3->irb#3 on #<Foo:0x4010af3c> (#<Thread:0x4010a1e0> : running)
# evaluate f.foo
irb.3(<Foo:0x4010af3c>):002:0> foo #=> 1 => nil
# evaluate f.bar
irb.3(<Foo:0x4010af3c>):003:0> bar #=> bar => nil
# kill jobs 1, 2, and 3
irb.3(<Foo:0x4010af3c>):004:0> kill 1, 2, 3
# list open sessions, should only include main session
irb(main):009:0> jobs
  #0->irb on main (#<Thread:0x400fb7e4> : running)
# quit irb
irb(main):010:0> exit

Constant Summary

Class Method Summary

Class Method Details

.conf

Displays current configuration.

Modifying the configuration is achieved by sending a message to conf.

See IRB@Configuration for more information.

[ GitHub ]

  
# File 'lib/irb.rb', line 367

def IRB.conf
  @CONF
end

CurrentContext

The current ::IRB::Context of the session, see .conf

irb
irb(main):001:0> IRB.CurrentContext.irb_name = "foo"
foo(main):002:0> IRB.conf[:MAIN_CONTEXT].irb_name #=> "foo"

See additional method definition at file lib/irb.rb line 384.

[ GitHub ]

  
# File 'lib/irb/ext/multi-irb.rb', line 181

def IRB.CurrentContext
  IRB.conf[:MAIN_CONTEXT]
end

.default_src_encoding

[ GitHub ]

  
# File 'lib/irb/src_encoding.rb', line 4

def self.default_src_encoding
  return __ENCODING__
end

.delete_caller

This method is for internal use only.
[ GitHub ]

  
# File 'lib/irb/workspace.rb', line 178

def IRB.delete_caller
end

.easter_egg(type = nil)

[ GitHub ]

  
# File 'lib/irb/easter-egg.rb', line 101

private def easter_egg(type = nil)
  type ||= [:, :dancing].sample
  case type
  when :
    File.open(File.join(__dir__, 'ruby_logo.aa')) do |f|
      require "rdoc"
      RDoc::RI::Driver.new.page do |io|
        IO.copy_stream(f, io)
      end
    end
  when :dancing
    begin
      canvas = Canvas.new(Reline.get_screen_size)
      Reline::IOGate.set_winch_handler do
        canvas = Canvas.new(Reline.get_screen_size)
      end
      ruby_model = RubyModel.new
      print "\e[?1049h"
      0.step do |i| # TODO (0..).each needs Ruby 2.6 or later
        buff = canvas.draw do
          ruby_model.render_frame(i) do |p1, p2|
            canvas.line(p1, p2)
          end
        end
        buff[0, 20] = "\e[0mPress Ctrl+C to stop\e[31m\e[1m"
        print "\e[H" + buff
        sleep 0.05
      end
    rescue Interrupt
    ensure
      print "\e[0m\e[?1049l"
    end
  end
end

.init_config(ap_path)

This method is for internal use only.
[ GitHub ]

  
# File 'lib/irb/init.rb', line 29

def IRB.init_config(ap_path)
  # class instance variables
  @TRACER_INITIALIZED = false

  # default configurations
  unless ap_path and @CONF[:AP_NAME]
    ap_path = File.join(File.dirname(File.dirname(__FILE__)), "irb.rb")
  end
  @CONF[:AP_NAME] = File::basename(ap_path, ".rb")

  @CONF[:IRB_NAME] = "irb"
  @CONF[:IRB_LIB_PATH] = File.dirname(__FILE__)

  @CONF[:RC] = true
  @CONF[:LOAD_MODULES] = []
  @CONF[:IRB_RC] = nil

  @CONF[:USE_SINGLELINE] = false unless defined?(ReadlineInputMethod)
  @CONF[:USE_COLORIZE] = true
  @CONF[:INSPECT_MODE] = true
  @CONF[:USE_TRACER] = false
  @CONF[:USE_LOADER] = false
  @CONF[:IGNORE_SIGINT] = true
  @CONF[:IGNORE_EOF] = false
  @CONF[:ECHO] = nil
  @CONF[:ECHO_ON_ASSIGNMENT] = nil
  @CONF[:VERBOSE] = nil

  @CONF[:EVAL_HISTORY] = nil
  @CONF[:SAVE_HISTORY] = 1000

  @CONF[:BACK_TRACE_LIMIT] = 16

  @CONF[:PROMPT] = {
    :NULL => {
      :PROMPT_I => nil,
      :PROMPT_N => nil,
      :PROMPT_S => nil,
      :PROMPT_C => nil,
      :RETURN => "%s\n"
    },
    :DEFAULT => {
      :PROMPT_I => "%N(%m):%03n:%i> ",
      :PROMPT_N => "%N(%m):%03n:%i> ",
      :PROMPT_S => "%N(%m):%03n:%i%l ",
      :PROMPT_C => "%N(%m):%03n:%i* ",
      :RETURN => "=> %s\n"
    },
    :CLASSIC => {
      :PROMPT_I => "%N(%m):%03n:%i> ",
      :PROMPT_N => "%N(%m):%03n:%i> ",
      :PROMPT_S => "%N(%m):%03n:%i%l ",
      :PROMPT_C => "%N(%m):%03n:%i* ",
      :RETURN => "%s\n"
    },
    :SIMPLE => {
      :PROMPT_I => ">> ",
      :PROMPT_N => ">> ",
      :PROMPT_S => "%l> ",
      :PROMPT_C => "?> ",
      :RETURN => "=> %s\n"
    },
    :INF_RUBY => {
      :PROMPT_I => "%N(%m):%03n:%i> ",
      :PROMPT_N => nil,
      :PROMPT_S => nil,
      :PROMPT_C => nil,
      :RETURN => "%s\n",
      :AUTO_INDENT => true
    },
    :XMP => {
      :PROMPT_I => nil,
      :PROMPT_N => nil,
      :PROMPT_S => nil,
      :PROMPT_C => nil,
      :RETURN => "    ==>%s\n"
    }
  }

  @CONF[:PROMPT_MODE] = (STDIN.tty? ? :DEFAULT : :NULL)
  @CONF[:AUTO_INDENT] = true

  @CONF[:CONTEXT_MODE] = 3 # use binding in function on TOPLEVEL_BINDING
  @CONF[:SINGLE_IRB] = false

  @CONF[:LC_MESSAGES] = Locale.new

  @CONF[:AT_EXIT] = []
end

.init_error

This method is for internal use only.
[ GitHub ]

  
# File 'lib/irb/init.rb', line 119

def IRB.init_error
  @CONF[:LC_MESSAGES].load("irb/error.rb")
end

.initialize_tracer

initialize tracing function

[ GitHub ]

  
# File 'lib/irb/ext/tracer.rb', line 30

def IRB.initialize_tracer
  Tracer.verbose = false
  Tracer.add_filter {
    |event, file, line, id, binding, *rests|
    /^#{Regexp.quote(@CONF[:IRB_LIB_PATH])}/ !~ file and
      File::basename(file) != "irb.rb"
  }
end

.inspect

[ GitHub ]

  
# File 'lib/irb.rb', line 820

def @CONF.inspect
  IRB.version unless self[:VERSION]

  array = []
  for k, v in sort{|a1, a2| a1[0].id2name <=> a2[0].id2name}
    case k
    when :MAIN_CONTEXT, :__TMP__EHV__
      array.push format("CONF[:%s]=...myself...", k.id2name)
    when :PROMPT
      s = v.collect{
        |kk, vv|
        ss = vv.collect{|kkk, vvv| ":#{kkk.id2name}=>#{vvv.inspect}"}
        format(":%s=>{%s}", kk.id2name, ss.join(", "))
      }
      array.push format("CONF[:%s]={%s}", k.id2name, s.join(", "))
    else
      array.push format("CONF[:%s]=%s", k.id2name, v.inspect)
    end
  end
  array.join("\n")
end

Inspector(inspect, init = nil)

This method is for internal use only.

Convenience method to create a new ::IRB::Inspector, using the given .inspect proc, and optional init proc and passes them to Inspector.new

irb(main):001:0> ins = IRB::Inspector(proc{ |v| "omg! #{v}" })
irb(main):001:0> IRB.CurrentContext.inspect_mode = ins # => omg! #<IRB::Inspector:0x007f46f7ba7d28>
irb(main):001:0> "what?" #=> omg! what?
[ GitHub ]

  
# File 'lib/irb/inspector.rb', line 24

def IRB::Inspector(inspect, init = nil)
  Inspector.new(inspect, init)
end

.irb(file = nil, *main)

Creates a new IRB session, see Irb.new.

The optional file argument is given to Context.new, along with the workspace created with the remaining arguments, see WorkSpace.new

[ GitHub ]

  
# File 'lib/irb/ext/multi-irb.rb', line 189

def IRB.irb(file = nil, *main)
  workspace = WorkSpace.new(*main)
  parent_thread = Thread.current
  Thread.start do
    begin
      irb = Irb.new(workspace, file)
    rescue
      print "Subirb can't start with context(self): ", workspace.main.inspect, "\n"
      print "return to main irb\n"
      Thread.pass
      Thread.main.wakeup
      Thread.exit
    end
    @CONF[:IRB_RC].call(irb.context) if @CONF[:IRB_RC]
    @JobManager.insert(irb)
    @JobManager.current_job = irb
    begin
      system_exit = false
      catch(:IRB_EXIT) do
        irb.eval_input
      end
    rescue SystemExit
      system_exit = true
      raise
      #fail
    ensure
      unless system_exit
        @JobManager.delete(irb)
        if @JobManager.current_job == irb
          if parent_thread.alive?
            @JobManager.current_job = @JobManager.irb(parent_thread)
            parent_thread.run
          else
            @JobManager.current_job = @JobManager.main_irb
            @JobManager.main_thread.run
          end
        end
      end
    end
  end
  Thread.stop
  @JobManager.current_job = @JobManager.irb(Thread.current)
end

.irb_abort(irb, exception = Abort)

Aborts then interrupts irb.

Will raise an ::IRB::Abort exception, or the given exception.

[ GitHub ]

  
# File 'lib/irb.rb', line 416

def IRB.irb_abort(irb, exception = Abort)
  if defined? Thread
    irb.context.thread.raise exception, "abort then interrupt!"
  else
    raise exception, "abort then interrupt!"
  end
end

.irb_at_exit

Calls each event hook of IRB.conf[:AT_EXIT] when the current session quits.

[ GitHub ]

  
# File 'lib/irb.rb', line 404

def IRB.irb_at_exit
  @CONF[:AT_EXIT].each{|hook| hook.call}
end

.irb_exit(irb, ret)

Quits irb

[ GitHub ]

  
# File 'lib/irb.rb', line 409

def IRB.irb_exit(irb, ret)
  throw :IRB_EXIT, ret
end

JobManager

The current ::IRB::JobManager in the session

[ GitHub ]

  
# File 'lib/irb/ext/multi-irb.rb', line 176

def IRB.JobManager
  @JobManager
end

.load_modules

This method is for internal use only.

loading modules

[ GitHub ]

  
# File 'lib/irb/init.rb', line 296

def IRB.load_modules
  for m in @CONF[:LOAD_MODULES]
    begin
      require m
    rescue LoadError => err
      warn "#{err.class}: #{err}", uplevel: 0
    end
  end
end

.parse_opts(argv: ::ARGV)

This method is for internal use only.

option analyzing

[ GitHub ]

  
# File 'lib/irb/init.rb', line 124

def IRB.parse_opts(argv: ::ARGV)
  load_path = []
  while opt = argv.shift
    case opt
    when "-f"
      @CONF[:RC] = false
    when "-d"
      $DEBUG = true
      $VERBOSE = true
    when "-w"
      $VERBOSE = true
    when /^-W(.+)?/
      opt = $1 || argv.shift
      case opt
      when "0"
        $VERBOSE = nil
      when "1"
        $VERBOSE = false
      else
        $VERBOSE = true
      end
    when /^-r(.+)?/
      opt = $1 || argv.shift
      @CONF[:LOAD_MODULES].push opt if opt
    when /^-I(.+)?/
      opt = $1 || argv.shift
      load_path.concat(opt.split(File::PATH_SEPARATOR)) if opt
    when '-U'
      set_encoding("UTF-8", "UTF-8")
    when /^-E(.+)?/, /^--encoding(?:=(.+))?/
      opt = $1 || argv.shift
      set_encoding(*opt.split(':', 2))
    when "--inspect"
      if /^-/ !~ argv.first
        @CONF[:INSPECT_MODE] = argv.shift
      else
        @CONF[:INSPECT_MODE] = true
      end
    when "--noinspect"
      @CONF[:INSPECT_MODE] = false
    when "--singleline", "--readline", "--legacy"
      @CONF[:USE_SINGLELINE] = true
    when "--nosingleline", "--noreadline"
      @CONF[:USE_SINGLELINE] = false
    when "--multiline", "--reidline"
      @CONF[:USE_MULTILINE] = true
    when "--nomultiline", "--noreidline"
      @CONF[:USE_MULTILINE] = false
    when "--echo"
      @CONF[:ECHO] = true
    when "--noecho"
      @CONF[:ECHO] = false
    when "--echo-on-assignment"
      @CONF[:ECHO_ON_ASSIGNMENT] = true
    when "--noecho-on-assignment"
      @CONF[:ECHO_ON_ASSIGNMENT] = false
    when "--truncate-echo-on-assignment"
      @CONF[:ECHO_ON_ASSIGNMENT] = :truncate
    when "--verbose"
      @CONF[:VERBOSE] = true
    when "--noverbose"
      @CONF[:VERBOSE] = false
    when "--colorize"
      @CONF[:USE_COLORIZE] = true
    when "--nocolorize"
      @CONF[:USE_COLORIZE] = false
    when /^--prompt-mode(?:=(.+))?/, /^--prompt(?:=(.+))?/
      opt = $1 || argv.shift
      prompt_mode = opt.upcase.tr("-", "_").intern
      @CONF[:PROMPT_MODE] = prompt_mode
    when "--noprompt"
      @CONF[:PROMPT_MODE] = :NULL
    when "--inf-ruby-mode"
      @CONF[:PROMPT_MODE] = :INF_RUBY
    when "--sample-book-mode", "--simple-prompt"
      @CONF[:PROMPT_MODE] = :SIMPLE
    when "--tracer"
      @CONF[:USE_TRACER] = true
    when /^--back-trace-limit(?:=(.+))?/
      @CONF[:BACK_TRACE_LIMIT] = ($1 || argv.shift).to_i
    when /^--context-mode(?:=(.+))?/
      @CONF[:CONTEXT_MODE] = ($1 || argv.shift).to_i
    when "--single-irb"
      @CONF[:SINGLE_IRB] = true
    when "-v", "--version"
      print IRB.version, "\n"
      exit 0
    when "-h", "--help"
      require_relative "help"
      IRB.print_usage
      exit 0
    when "--"
      if opt = argv.shift
        @CONF[:SCRIPT] = opt
        $0 = opt
      end
      break
    when /^-/
      fail UnrecognizedSwitch, opt
    else
      @CONF[:SCRIPT] = opt
      $0 = opt
      break
    end
  end
  load_path.collect! do |path|
    /\A\.\// =~ path ? path : File.expand_path(path)
  end
  $LOAD_PATH.unshift(*load_path)

end

.rc_file(ext = IRBRC_EXT)

This method is for internal use only.
[ GitHub ]

  
# File 'lib/irb/init.rb', line 253

def IRB.rc_file(ext = IRBRC_EXT)
  if !@CONF[:RC_NAME_GENERATOR]
    rc_file_generators do |rcgen|
      @CONF[:RC_NAME_GENERATOR] ||= rcgen
      if File.exist?(rcgen.call(IRBRC_EXT))
        @CONF[:RC_NAME_GENERATOR] = rcgen
        break
      end
    end
  end
  case rc_file = @CONF[:RC_NAME_GENERATOR].call(ext)
  when String
    return rc_file
  else
    fail IllegalRCNameGenerator
  end
end

.rc_file_generators {|proc{|rc| current_dir+"/.config/irb/irb#{rc}"}| ... }

This method is for internal use only.

enumerate possible rc-file base name generators

Yields:

  • (proc{|rc| current_dir+"/.config/irb/irb#{rc}"})
[ GitHub ]

  
# File 'lib/irb/init.rb', line 272

def IRB.rc_file_generators
  if irbrc = ENV["IRBRC"]
    yield proc{|rc| rc == "rc" ? irbrc : irbrc+rc}
  end
  if xdg_config_home = ENV["XDG_CONFIG_HOME"]
    irb_home = File.join(xdg_config_home, "irb")
    unless File.exist? irb_home
      require 'fileutils'
      FileUtils.mkdir_p irb_home
    end
    yield proc{|rc| irb_home + "/irb#{rc}"}
  end
  if home = ENV["HOME"]
    yield proc{|rc| home+"/.irb#{rc}"}
  end
  current_dir = Dir.pwd
  yield proc{|rc| current_dir+"/.config/irb/irb#{rc}"}
  yield proc{|rc| current_dir+"/.irb#{rc}"}
  yield proc{|rc| current_dir+"/irb#{rc.sub(/\A_?/, '.')}"}
  yield proc{|rc| current_dir+"/_irb#{rc}"}
  yield proc{|rc| current_dir+"/$irb#{rc}"}
end

.run_config

This method is for internal use only.

running config

[ GitHub ]

  
# File 'lib/irb/init.rb', line 237

def IRB.run_config
  if @CONF[:RC]
    begin
      load rc_file
    rescue LoadError, Errno::ENOENT
    rescue # StandardError, ScriptError
      print "load error: #{rc_file}\n"
      print $!.class, ": ", $!, "\n"
      for err in $@[0, $@.size - 2]
        print "\t", err, "\n"
      end
    end
  end
end

.set_encoding(extern, intern = nil, override: true) (private)

This method is for internal use only.
[ GitHub ]

  
# File 'lib/irb/init.rb', line 310

def set_encoding(extern, intern = nil, override: true)
  verbose, $VERBOSE = $VERBOSE, nil
  Encoding.default_external = extern unless extern.nil? || extern.empty?
  Encoding.default_internal = intern unless intern.nil? || intern.empty?
  [$stdin, $stdout, $stderr].each do |io|
    io.set_encoding(extern, intern)
  end
  if override
    @CONF[:LC_MESSAGES].instance_variable_set(:@override_encoding, extern)
  else
    @CONF[:LC_MESSAGES].instance_variable_set(:@encoding, extern)
  end
ensure
  $VERBOSE = verbose
end

.setup(ap_path, argv: ::ARGV)

This method is for internal use only.

initialize config

[ GitHub ]

  
# File 'lib/irb/init.rb', line 16

def IRB.setup(ap_path, argv: ::ARGV)
  IRB.init_config(ap_path)
  IRB.init_error
  IRB.parse_opts(argv: argv)
  IRB.run_config
  IRB.load_modules

  unless @CONF[:PROMPT][@CONF[:PROMPT_MODE]]
    fail UndefinedPromptMode, @CONF[:PROMPT_MODE]
  end
end

.start(ap_path = nil)

Initializes IRB and creates a new Irb.irb object at the TOPLEVEL_BINDING

[ GitHub ]

  
# File 'lib/irb.rb', line 389

def IRB.start(ap_path = nil)
  STDOUT.sync = true
  $0 = File::basename(ap_path, ".rb") if ap_path

  IRB.setup(ap_path)

  if @CONF[:SCRIPT]
    irb = Irb.new(nil, @CONF[:SCRIPT])
  else
    irb = Irb.new
  end
  irb.run(@CONF)
end

.version

Returns the current version of IRB, including release version and last updated date.

[ GitHub ]

  
# File 'lib/irb.rb', line 373

def IRB.version
  if v = @CONF[:VERSION] then return v end

  @CONF[:VERSION] = format("irb %s (%s)", @RELEASE_VERSION, @LAST_UPDATE_DATE)
end