class IRB::Context

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

Constants

KEYWORD_ALIASES: because all input will eventually be evaluated as Ruby code, command names that conflict with Ruby keywords need special workaround we can remove them once we implemented a better command system for IRB

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

irb_context.auto_indent_mode = false

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

irb_context.echo_on_assignment = :truncate or true or false

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

irb_context.echo_on_assignment = :truncate or true or false

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 lib/irb/context.rb, line 23
    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]

      if IRB.conf[:SINGLE_IRB] or !defined?(IRB::JobManager)
        @irb_name = IRB.conf[:IRB_NAME]
      else
        @irb_name = IRB.conf[: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 STDIN.tty? && 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) && STDIN.tty? &&
                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

      @user_aliases = IRB.conf[:COMMAND_ALIASES].dup
      @command_aliases = @user_aliases.merge(KEYWORD_ALIASES)
    end

Public Instance Methods

_set_last_value(value)

See set_last_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 lib/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

eval_history=(val) click to toggle source

# File lib/irb/context.rb, line 170
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 lib/irb/context.rb, line 530
def file_input?
  @io.class == FileInputMethod
end

history_file() click to toggle source

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

# File lib/irb/context.rb, line 224
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 lib/irb/context.rb, line 229
def history_file=(hist)
  IRB.conf[:HISTORY_FILE] = hist
end

home_workspace() click to toggle source

Inherited from TOPLEVEL_BINDING.

# File lib/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 lib/irb/context.rb, line 524
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 lib/irb/context.rb, line 545
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 lib/irb/context.rb, line 283
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 lib/irb/context.rb, line 245
def main
  workspace.main
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 lib/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 lib/irb/context.rb, line 508
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 lib/irb/context.rb, line 324
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 lib/irb/context.rb, line 330
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 lib/irb/context.rb, line 491
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 lib/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 lib/irb/context.rb, line 239
def replace_workspace(workspace)
  @workspace_stack.pop
  @workspace_stack.push(workspace)
end

save_history() click to toggle source

# File lib/irb/context.rb, line 219
def save_history
  IRB.conf[:SAVE_HISTORY]
end

save_history=(val) click to toggle source

# File lib/irb/context.rb, line 215
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 lib/irb/context.rb, line 500
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 lib/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 lib/irb/context.rb, line 176
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 lib/irb/context.rb, line 165
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 lib/irb/context.rb, line 472
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 lib/irb/context.rb, line 234
def workspace
  @workspace_stack.last
end

Private Instance Methods

build_completor() click to toggle source

# File lib/irb/context.rb, line 182
        def build_completor
  completor_type = IRB.conf[:COMPLETOR]
  case completor_type
  when :regexp
    return RegexpCompletor.new
  when :type
    completor = build_type_completor
    return completor if completor
  else
    warn "Invalid value for IRB.conf[:COMPLETOR]: #{completor_type}"
  end
  # Fallback to RegexpCompletor
  RegexpCompletor.new
end

build_type_completor() click to toggle source

# File lib/irb/context.rb, line 197
        def build_type_completor
  if RUBY_ENGINE == 'truffleruby'
    # Avoid SyntaxError. truffleruby does not support endless method definition yet.
    warn 'TypeCompletor is not supported on TruffleRuby yet'
    return
  end

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

  ReplTypeCompletor.preload_rbs
  TypeCompletor.new(self)
end