class IRB::Context

A class that wraps the current state of the irb session, including the configuration of IRB.conf.

Constants

ASSIGN_OPERATORS_REGEXP
KERNEL_METHOD
KERNEL_PUBLIC_METHOD

Attributes

ap_name[RW]

A copy of the default IRB.conf[:AP_NAME]

auto_indent_mode[RW]

Can be either the default IRB.conf[:AUTO_INDENT], or the mode set by prompt_mode=

To disable auto-indentation in irb:

IRB.conf[:AUTO_INDENT] = false

or

irb_context.auto_indent_mode = false

or

IRB.CurrentContext.auto_indent_mode = false

See Configuration at IRB for more information.

back_trace_limit[RW]

The limit of backtrace lines displayed as top n and tail n.

The default value is 16.

Can also be set using the --back-trace-limit command line option.

command_aliases[RW]

User-defined IRB command aliases

echo[RW]

Whether to echo the return value to output or not.

Uses IRB.conf[:ECHO] if available, or defaults to true.

puts "hello"
# hello
#=> nil
IRB.CurrentContext.echo = false
puts "omg"
# omg
echo?[RW]

Whether to echo the return value to output or not.

Uses IRB.conf[:ECHO] if available, or defaults to true.

puts "hello"
# hello
#=> nil
IRB.CurrentContext.echo = false
puts "omg"
# omg
echo_on_assignment[RW]

Whether to echo for assignment expressions.

If set to false, the value of assignment will not be shown.

If set to true, the value of assignment will be shown.

If set to :truncate, the value of assignment will be shown and truncated.

It defaults to :truncate.

a = "omg"
#=> omg

a = "omg" * 10
#=> omgomgomgomgomgomgomg...

IRB.CurrentContext.echo_on_assignment = false
a = "omg"

IRB.CurrentContext.echo_on_assignment = true
a = "omg" * 10
#=> omgomgomgomgomgomgomgomgomgomg

To set the behaviour of showing on assignment in irb:

IRB.conf[:ECHO_ON_ASSIGNMENT] = :truncate or true or false

or

irb_context.echo_on_assignment = :truncate or true or false

or

IRB.CurrentContext.echo_on_assignment = :truncate or true or false
echo_on_assignment?[RW]

Whether to echo for assignment expressions.

If set to false, the value of assignment will not be shown.

If set to true, the value of assignment will be shown.

If set to :truncate, the value of assignment will be shown and truncated.

It defaults to :truncate.

a = "omg"
#=> omg

a = "omg" * 10
#=> omgomgomgomgomgomgomg...

IRB.CurrentContext.echo_on_assignment = false
a = "omg"

IRB.CurrentContext.echo_on_assignment = true
a = "omg" * 10
#=> omgomgomgomgomgomgomgomgomgomg

To set the behaviour of showing on assignment in irb:

IRB.conf[:ECHO_ON_ASSIGNMENT] = :truncate or true or false

or

irb_context.echo_on_assignment = :truncate or true or false

or

IRB.CurrentContext.echo_on_assignment = :truncate or true or false
eval_history[R]

The command result history limit. This method is not available until eval_history= was called with non-nil value (directly or via setting IRB.conf[:EVAL_HISTORY] in .irbrc).

extra_doc_dirs[RW]

Specify the installation locations of the ri file to be displayed in the document dialog.

ignore_eof[RW]

Whether ^D (control-d) will be ignored or not.

If set to false, ^D will quit irb.

ignore_eof?[RW]

Whether ^D (control-d) will be ignored or not.

If set to false, ^D will quit irb.

ignore_sigint[RW]

Whether ^C (control-c) will be ignored or not.

If set to false, ^C will quit irb.

If set to true,

  • during input: cancel input then return to top level.

  • during execute: abandon current execution.

ignore_sigint?[RW]

Whether ^C (control-c) will be ignored or not.

If set to false, ^C will quit irb.

If set to true,

  • during input: cancel input then return to top level.

  • during execute: abandon current execution.

inspect_mode[R]

A copy of the default IRB.conf[:INSPECT_MODE]

io[RW]

The current input method.

Can be either StdioInputMethod, ReadlineInputMethod, RelineInputMethod, FileInputMethod or other specified when the context is created. See ::new for more # information on input_method.

irb[RW]

Current irb session.

irb_name[RW]

Can be either name from IRB.conf[:IRB_NAME], or the number of the current job set by JobManager, such as irb#2

irb_path[R]

Can be one of the following:

  • the irb_name surrounded by parenthesis

  • the input_method passed to Context.new

  • the file path of the current IRB context in a binding.irb session

last_value[R]

The return value of the last statement evaluated.

load_modules[RW]

A copy of the default IRB.conf[:LOAD_MODULES]

newline_before_multiline_output[RW]

Whether a newline is put before multiline output.

Uses IRB.conf[:NEWLINE_BEFORE_MULTILINE_OUTPUT] if available, or defaults to true.

"abc\ndef"
#=>
abc
def
IRB.CurrentContext.newline_before_multiline_output = false
"abc\ndef"
#=> abc
def
newline_before_multiline_output?[RW]

Whether a newline is put before multiline output.

Uses IRB.conf[:NEWLINE_BEFORE_MULTILINE_OUTPUT] if available, or defaults to true.

"abc\ndef"
#=>
abc
def
IRB.CurrentContext.newline_before_multiline_output = false
"abc\ndef"
#=> abc
def
prompt_c[RW]

IRB prompt for continuated statement. (e.g. immediately after an if)

See Custom Prompts for more information.

prompt_i[RW]

Standard IRB prompt.

See Custom Prompts for more information.

prompt_mode[R]

A copy of the default IRB.conf[:PROMPT_MODE]

prompt_s[RW]

IRB prompt for continuated strings.

See Custom Prompts for more information.

rc[RW]

A copy of the default IRB.conf[:RC]

rc?[RW]

A copy of the default IRB.conf[:RC]

return_format[RW]

The format of the return statement, set by prompt_mode= using the :RETURN of the mode passed to set the current prompt_mode.

thread[R]

The current thread in this context.

use_autocomplete[R]

Whether colorization is enabled or not.

A copy of the default IRB.conf[:USE_AUTOCOMPLETE]

use_autocomplete?[R]

Whether colorization is enabled or not.

A copy of the default IRB.conf[:USE_AUTOCOMPLETE]

use_multiline[R]

Whether multiline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_MULTILINE]

use_multiline?[R]

Whether multiline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_MULTILINE]

use_readline[R]

Whether singleline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_SINGLELINE]

use_readline?[R]

Whether singleline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_SINGLELINE]

use_reline[R]

Whether multiline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_MULTILINE]

use_reline?[R]

Whether multiline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_MULTILINE]

use_singleline[R]

Whether singleline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_SINGLELINE]

use_singleline?[R]

Whether singleline editor mode is enabled or not.

A copy of the default IRB.conf[:USE_SINGLELINE]

verbose[RW]

Whether verbose messages are displayed or not.

A copy of the default IRB.conf[:VERBOSE]

with_debugger[RW]
workspace_home[R]

The toplevel workspace, see home_workspace

Public Class Methods

new(irb, workspace = nil, input_method = nil) click to toggle source

Creates a new IRB context.

The optional input_method argument:

nil

uses stdin or Reline or Readline

String

uses a File

other

uses this as InputMethod

# File irb/context.rb, line 27
    def initialize(irb, workspace = nil, input_method = nil)
      @irb = irb
      @workspace_stack = []
      if workspace
        @workspace_stack << workspace
      else
        @workspace_stack << WorkSpace.new
      end
      @thread = Thread.current

      # copy of default configuration
      @ap_name = IRB.conf[:AP_NAME]
      @rc = IRB.conf[:RC]
      @load_modules = IRB.conf[:LOAD_MODULES]

      if IRB.conf.has_key?(:USE_SINGLELINE)
        @use_singleline = IRB.conf[:USE_SINGLELINE]
      elsif IRB.conf.has_key?(:USE_READLINE) # backward compatibility
        @use_singleline = IRB.conf[:USE_READLINE]
      else
        @use_singleline = nil
      end
      if IRB.conf.has_key?(:USE_MULTILINE)
        @use_multiline = IRB.conf[:USE_MULTILINE]
      elsif IRB.conf.has_key?(:USE_RELINE) # backward compatibility
        warn <<~MSG.strip
          USE_RELINE is deprecated, please use USE_MULTILINE instead.
        MSG
        @use_multiline = IRB.conf[:USE_RELINE]
      elsif IRB.conf.has_key?(:USE_REIDLINE)
        warn <<~MSG.strip
          USE_REIDLINE is deprecated, please use USE_MULTILINE instead.
        MSG
        @use_multiline = IRB.conf[:USE_REIDLINE]
      else
        @use_multiline = nil
      end
      @use_autocomplete = IRB.conf[:USE_AUTOCOMPLETE]
      @verbose = IRB.conf[:VERBOSE]
      @io = nil

      self.inspect_mode = IRB.conf[:INSPECT_MODE]
      self.use_tracer = IRB.conf[:USE_TRACER]
      self.use_loader = IRB.conf[:USE_LOADER] if IRB.conf[:USE_LOADER]
      self.eval_history = IRB.conf[:EVAL_HISTORY] if IRB.conf[:EVAL_HISTORY]

      @ignore_sigint = IRB.conf[:IGNORE_SIGINT]
      @ignore_eof = IRB.conf[:IGNORE_EOF]

      @back_trace_limit = IRB.conf[:BACK_TRACE_LIMIT]

      self.prompt_mode = IRB.conf[:PROMPT_MODE]

      @irb_name = IRB.conf[:IRB_NAME]

      unless IRB.conf[:SINGLE_IRB] or !defined?(IRB::JobManager)
        @irb_name = @irb_name + "#" + IRB.JobManager.n_jobs.to_s
      end

      self.irb_path = "(" + @irb_name + ")"

      case input_method
      when nil
        @io = nil
        case use_multiline?
        when nil
          if term_interactive? && IRB.conf[:PROMPT_MODE] != :INF_RUBY && !use_singleline?
            # Both of multiline mode and singleline mode aren't specified.
            @io = RelineInputMethod.new(build_completor)
          else
            @io = nil
          end
        when false
          @io = nil
        when true
          @io = RelineInputMethod.new(build_completor)
        end
        unless @io
          case use_singleline?
          when nil
            if (defined?(ReadlineInputMethod) && term_interactive? &&
                IRB.conf[:PROMPT_MODE] != :INF_RUBY)
              @io = ReadlineInputMethod.new
            else
              @io = nil
            end
          when false
            @io = nil
          when true
            if defined?(ReadlineInputMethod)
              @io = ReadlineInputMethod.new
            else
              @io = nil
            end
          else
            @io = nil
          end
        end
        @io = StdioInputMethod.new unless @io

      when '-'
        @io = FileInputMethod.new($stdin)
        @irb_name = '-'
        self.irb_path = '-'
      when String
        @io = FileInputMethod.new(input_method)
        @irb_name = File.basename(input_method)
        self.irb_path = input_method
      else
        @io = input_method
      end
      @extra_doc_dirs = IRB.conf[:EXTRA_DOC_DIRS]

      @echo = IRB.conf[:ECHO]
      if @echo.nil?
        @echo = true
      end

      @echo_on_assignment = IRB.conf[:ECHO_ON_ASSIGNMENT]
      if @echo_on_assignment.nil?
        @echo_on_assignment = :truncate
      end

      @newline_before_multiline_output = IRB.conf[:NEWLINE_BEFORE_MULTILINE_OUTPUT]
      if @newline_before_multiline_output.nil?
        @newline_before_multiline_output = true
      end

      @command_aliases = IRB.conf[:COMMAND_ALIASES].dup
    end

Public Instance Methods

_set_last_value(value)
Alias for: set_last_value
change_workspace(*_main) click to toggle source

Changes the current workspace to given object or binding.

If the optional argument is omitted, the workspace will be home_workspace which is inherited from TOPLEVEL_BINDING or the main object, IRB.conf[:MAIN_CONTEXT] when irb was initialized.

See IRB::WorkSpace.new for more information.

# File irb/ext/change-ws.rb, line 26
def change_workspace(*_main)
  if _main.empty?
    replace_workspace(home_workspace)
    return main
  end

  workspace = WorkSpace.new(_main[0])
  replace_workspace(workspace)
  workspace.load_helper_methods_to_main
end
colorize_input(input, complete:) click to toggle source
# File irb/context.rb, line 661
def colorize_input(input, complete:)
  if IRB.conf[:USE_COLORIZE] && IRB::Color.colorable?
    lvars = local_variables || []
    if parse_command(input)
      name, sep, arg = input.split(/(\s+)/, 2)
      arg = IRB::Color.colorize_code(arg, complete: complete, local_variables: lvars)
      "#{IRB::Color.colorize(name, [:BOLD])}\e[m#{sep}#{arg}"
    else
      IRB::Color.colorize_code(input, complete: complete, local_variables: lvars)
    end
  else
    Reline::Unicode.escape_for_print(input)
  end
end
eval_history=(val) click to toggle source
# File irb/context.rb, line 168
def eval_history=(val)
  self.class.remove_method(__method__)
  require_relative "ext/eval_history"
  __send__(__method__, val)
end
file_input?() click to toggle source

Whether io uses a File for the input_method passed when creating the current context, see ::new

# File irb/context.rb, line 534
def file_input?
  @io.class == FileInputMethod
end
from_binding?() click to toggle source
# File irb/context.rb, line 608
def from_binding?
  @irb.from_binding
end
history_file() click to toggle source

A copy of the default IRB.conf[:HISTORY_FILE]

# File irb/context.rb, line 228
def history_file
  IRB.conf[:HISTORY_FILE]
end
history_file=(hist) click to toggle source

Set IRB.conf[:HISTORY_FILE] to the given hist.

# File irb/context.rb, line 233
def history_file=(hist)
  IRB.conf[:HISTORY_FILE] = hist
end
home_workspace() click to toggle source

Inherited from TOPLEVEL_BINDING.

# File irb/ext/change-ws.rb, line 11
def home_workspace
  if defined? @home_workspace
    @home_workspace
  else
    @home_workspace = workspace
  end
end
inspect?() click to toggle source

Whether inspect_mode is set or not, see inspect_mode= for more detail.

# File irb/context.rb, line 528
def inspect?
  @inspect_mode.nil? or @inspect_mode
end
inspect_mode=(opt) click to toggle source

Specifies the inspect mode with opt:

true

display inspect

false

display to_s

nil

inspect mode in non-math mode, non-inspect mode in math mode

See IRB::Inspector for more information.

Can also be set using the --inspect and --noinspect command line options.

# File irb/context.rb, line 549
def inspect_mode=(opt)

  if i = Inspector::INSPECTORS[opt]
    @inspect_mode = opt
    @inspect_method = i
    i.init
  else
    case opt
    when nil
      if Inspector.keys_with_inspector(Inspector::INSPECTORS[true]).include?(@inspect_mode)
        self.inspect_mode = false
      elsif Inspector.keys_with_inspector(Inspector::INSPECTORS[false]).include?(@inspect_mode)
        self.inspect_mode = true
      else
        puts "Can't switch inspect mode."
        return
      end
    when /^\s*\{.*\}\s*$/
      begin
        inspector = eval "proc#{opt}"
      rescue Exception
        puts "Can't switch inspect mode(#{opt})."
        return
      end
      self.inspect_mode = inspector
    when Proc
      self.inspect_mode = IRB::Inspector(opt)
    when Inspector
      prefix = "usr%d"
      i = 1
      while Inspector::INSPECTORS[format(prefix, i)]; i += 1; end
      @inspect_mode = format(prefix, i)
      @inspect_method = opt
      Inspector.def_inspector(format(prefix, i), @inspect_method)
    else
      puts "Can't switch inspect mode(#{opt})."
      return
    end
  end
  print "Switch to#{unless @inspect_mode; ' non';end} inspect mode.\n" if verbose?
  @inspect_mode
end
irb_path=(path) click to toggle source

Sets @irb_path to the given path as well as @eval_path @eval_path is used for evaluating code in the context of IRB session It’s the same as irb_path, but with the IRB name postfix This makes sure users can distinguish the methods defined in the IRB session from the methods defined in the current file’s context, especially with binding.irb

# File irb/context.rb, line 287
def irb_path=(path)
  @irb_path = path

  if File.exist?(path)
    @eval_path = "#{path}(#{IRB.conf[:IRB_NAME]})"
  else
    @eval_path = path
  end
end
main() click to toggle source

The top-level workspace, see WorkSpace#main

# File irb/context.rb, line 249
def main
  workspace.main
end
parse_command(code) click to toggle source
# File irb/context.rb, line 636
def parse_command(code)
  command_name, arg = code.strip.split(/\s+/, 2)
  return unless code.lines.size == 1 && command_name

  arg ||= ''
  command = command_name.to_sym
  # Command aliases are always command. example: $, @
  if (alias_name = command_aliases[command])
    return [alias_name, arg]
  end

  # Assignment-like expression is not a command
  return if arg.start_with?(ASSIGN_OPERATORS_REGEXP) && !arg.start_with?(/==|=~/)

  # Local variable have precedence over command
  return if local_variables.include?(command)

  # Check visibility
  public_method = !!KERNEL_PUBLIC_METHOD.bind_call(main, command) rescue false
  private_method = !public_method && !!KERNEL_METHOD.bind_call(main, command) rescue false
  if Command.execute_as_command?(command, public_method: public_method, private_method: private_method)
    [command, arg]
  end
end
pop_workspace() click to toggle source

Removes the last element from the current workspaces stack and returns it, or nil if the current workspace stack is empty.

Also, see push_workspace.

# File irb/ext/workspaces.rb, line 32
def pop_workspace
  @workspace_stack.pop if @workspace_stack.size > 1
end
prompt_mode=(mode) click to toggle source

Sets the mode of the prompt in this context.

See Custom Prompts for more information.

# File irb/context.rb, line 512
def prompt_mode=(mode)
  @prompt_mode = mode
  pconf = IRB.conf[:PROMPT][mode]
  @prompt_i = pconf[:PROMPT_I]
  @prompt_s = pconf[:PROMPT_S]
  @prompt_c = pconf[:PROMPT_C]
  @return_format = pconf[:RETURN]
  @return_format = "%s\n" if @return_format == nil
  if ai = pconf.include?(:AUTO_INDENT)
    @auto_indent_mode = ai
  else
    @auto_indent_mode = IRB.conf[:AUTO_INDENT]
  end
end
prompt_n() click to toggle source

TODO: Remove this when developing v2.0

# File irb/context.rb, line 328
def prompt_n
  warn "IRB::Context#prompt_n is deprecated and will be removed in the next major release."
  ""
end
prompt_n=(_) click to toggle source

TODO: Remove this when developing v2.0

# File irb/context.rb, line 334
def prompt_n=(_)
  warn "IRB::Context#prompt_n= is deprecated and will be removed in the next major release."
  ""
end
prompting?() click to toggle source

Whether verbose? is true, and input_method is either StdioInputMethod or RelineInputMethod or ReadlineInputMethod, see io for more information.

# File irb/context.rb, line 495
def prompting?
  verbose? || @io.prompting?
end
push_workspace(*_main) click to toggle source

Creates a new workspace with the given object or binding, and appends it onto the current workspaces stack.

See IRB::Context#change_workspace and IRB::WorkSpace.new for more information.

# File irb/ext/workspaces.rb, line 14
def push_workspace(*_main)
  if _main.empty?
    if @workspace_stack.size > 1
      # swap the top two workspaces
      previous_workspace, current_workspace = @workspace_stack.pop(2)
      @workspace_stack.push current_workspace, previous_workspace
    end
  else
    new_workspace = WorkSpace.new(workspace.binding, _main[0])
    @workspace_stack.push new_workspace
    new_workspace.load_helper_methods_to_main
  end
end
replace_workspace(workspace) click to toggle source

Replace the current workspace with the given workspace.

# File irb/context.rb, line 243
def replace_workspace(workspace)
  @workspace_stack.pop
  @workspace_stack.push(workspace)
end
safe_method_call_on_main(method_name) click to toggle source
# File irb/context.rb, line 711
def safe_method_call_on_main(method_name)
  main_object = main
  Object === main_object ? main_object.__send__(method_name) : Object.instance_method(method_name).bind_call(main_object)
end
save_history() click to toggle source
# File irb/context.rb, line 223
def save_history
  IRB.conf[:SAVE_HISTORY]
end
save_history=(val) click to toggle source
# File irb/context.rb, line 219
def save_history=(val)
  IRB.conf[:SAVE_HISTORY] = val
end
set_last_value(value) click to toggle source

Sets the return value from the last statement evaluated in this context to last_value.

# File irb/context.rb, line 504
def set_last_value(value)
  @last_value = value
  workspace.local_variable_set :_, value
end
Also aliased as: _set_last_value
use_loader() click to toggle source

Returns whether irb‘s own file reader method is used by load/require or not.

This mode is globally affected (irb-wide).

# File irb/ext/use-loader.rb, line 37
def use_loader
  IRB.conf[:USE_LOADER]
end
Also aliased as: use_loader?
use_loader=(val) click to toggle source
# File irb/context.rb, line 174
def use_loader=(val)
  self.class.remove_method(__method__)
  require_relative "ext/use-loader"
  __send__(__method__, val)
end
use_loader?()
Alias for: use_loader
use_tracer=(val) click to toggle source
# File irb/context.rb, line 163
def use_tracer=(val)
  require_relative "ext/tracer" if val
  IRB.conf[:USE_TRACER] = val
end
verbose?() click to toggle source

Returns whether messages are displayed or not.

# File irb/context.rb, line 476
def verbose?
  if @verbose.nil?
    if @io.kind_of?(RelineInputMethod)
      false
    elsif defined?(ReadlineInputMethod) && @io.kind_of?(ReadlineInputMethod)
      false
    elsif !STDIN.tty? or @io.kind_of?(FileInputMethod)
      true
    else
      false
    end
  else
    @verbose
  end
end
workspace() click to toggle source

Workspace in the current context.

# File irb/context.rb, line 238
def workspace
  @workspace_stack.last
end

Private Instance Methods

build_completor() click to toggle source
# File irb/context.rb, line 180
        def build_completor
  completor_type = IRB.conf[:COMPLETOR]

  # Gem repl_type_completor is added to bundled gems in Ruby 3.4.
  # Use :type as default completor only in Ruby 3.4 or later.
  verbose = !!completor_type
  completor_type ||= RUBY_VERSION >= '3.4' ? :type : :regexp

  case completor_type
  when :regexp
    return RegexpCompletor.new
  when :type
    completor = build_type_completor(verbose: verbose)
    return completor if completor
  else
    warn "Invalid value for IRB.conf[:COMPLETOR]: #{completor_type}"
  end
  # Fallback to RegexpCompletor
  RegexpCompletor.new
end
build_type_completor(verbose:) click to toggle source
# File irb/context.rb, line 201
        def build_type_completor(verbose:)
  if RUBY_ENGINE == 'truffleruby'
    # Avoid SyntaxError. truffleruby does not support endless method definition yet.
    warn 'TypeCompletor is not supported on TruffleRuby yet' if verbose
    return
  end

  begin
    require 'repl_type_completor'
  rescue LoadError => e
    warn "TypeCompletor requires `gem repl_type_completor`: #{e.message}" if verbose
    return
  end

  ReplTypeCompletor.preload_rbs
  TypeCompletor.new(self)
end
term_interactive?() click to toggle source
# File irb/context.rb, line 158
        def term_interactive?
  return true if ENV['TEST_IRB_FORCE_INTERACTIVE']
  STDIN.tty? && ENV['TERM'] != 'dumb'
end