Class: IRB::Context (Ruby 2.3.4)

IRB::Context

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

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 enable auto-indentation in irb:

IRB.conf[:AUTO_INDENT] = true

or

irb_context.auto_indent_mode = true

or

IRB.CurrentContext.auto_indent_mode = true

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.

See Command line options at IRB for more command line options.

debug_level[R]

The debug level of irb

See debug_level= for more information.

echo[RW]

Whether to echo the return value to output or not.

Uses IRB.conf 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 if available, or defaults to true.

puts "hello"
# hello
#=> nil
IRB.CurrentContext.echo = false
puts "omg"
# omg
eval_history[R]

The command result history limit.

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, 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[RW]

Can be either the irb_name surrounded by parenthesis, or the input_method passed to ::new

last_value[R]

The return value of the last statement evaluated.

load_modules[RW]

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

math?[R]

Returns whether bc mode is enabled.

See math_mode=

math_mode[R]

Returns whether bc mode is enabled.

See math_mode=

prompt_c[RW]

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

See IRB for more information.

prompt_i[RW]

Standard IRB prompt

See IRB for more information.

prompt_mode[R]

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

prompt_n[RW]

See Customizing the IRB Prompt at IRB for more information.

prompt_s[RW]

IRB prompt for continuated strings

See IRB 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_readline[R]

Whether Readline is enabled or not.

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

See use_readline= for more information.

use_readline?[R]

Whether Readline is enabled or not.

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

See use_readline= for more information.

use_tracer[R]

Whether Tracer is used when evaluating statements in this context.

See lib/tracer.rb for more information.

use_tracer?[R]

Whether Tracer is used when evaluating statements in this context.

See lib/tracer.rb for more information.

verbose[RW]

Whether verbose messages are displayed or not.

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

workspace[RW]

WorkSpace in the current context

workspace_home[R]

The toplevel workspace, see home_workspace

Public Class Methods

new(irb, workspace = nil, input_method = nil, output_method = nil)

Creates a new IRB context.

The optional input_method argument:

nil

uses stdin or Readline

String

uses a File

other

uses this as InputMethod

 
               # File irb/context.rb, line 26
def initialize(irb, workspace = nil, input_method = nil, output_method = nil)
  @irb = irb
  if workspace
    @workspace = workspace
  else
    @workspace = WorkSpace.new
  end
  @thread = Thread.current if defined? Thread

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

  @use_readline = IRB.conf[:USE_READLINE]
  @verbose = IRB.conf[:VERBOSE]
  @io = nil

  self.inspect_mode = IRB.conf[:INSPECT_MODE]
  self.math_mode = IRB.conf[:MATH_MODE] if IRB.conf[:MATH_MODE]
  self.use_tracer = IRB.conf[:USE_TRACER] if 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
  @irb_path = "(" + @irb_name + ")"

  case input_method
  when nil
    case use_readline?
    when nil
      if (defined?(ReadlineInputMethod) && STDIN.tty? &&
          IRB.conf[:PROMPT_MODE] != :INF_RUBY)
        @io = ReadlineInputMethod.new
      else
        @io = StdioInputMethod.new
      end
    when false
      @io = StdioInputMethod.new
    when true
      if defined?(ReadlineInputMethod)
        @io = ReadlineInputMethod.new
      else
        @io = StdioInputMethod.new
      end
    end

  when String
    @io = FileInputMethod.new(input_method)
    @irb_name = File.basename(input_method)
    @irb_path = input_method
  else
    @io = input_method
  end
  self.save_history = IRB.conf[:SAVE_HISTORY] if IRB.conf[:SAVE_HISTORY]

  if output_method
    @output_method = output_method
  else
    @output_method = StdioOutputMethod.new
  end

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

Public Instance Methods

__exit__(ret = 0)
Alias for: exit
_set_last_value(value)
Alias for: set_last_value
change_workspace(*_main)

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 32
def change_workspace(*_main)
  if _main.empty?
    @workspace = home_workspace
    return main
  end

  @workspace = WorkSpace.new(_main[0])

  if !(class<<main;ancestors;end).include?(ExtendCommandBundle)
    main.extend ExtendCommandBundle
  end
end
            
debug?()

Whether or not debug mode is enabled, see debug_level=.

 
               # File irb/context.rb, line 374
def debug?
  @debug_level > 0
end
            
debug_level=(value)

Sets the debug level of irb

Can also be set using the --irb_debug command line option.

See Command line options at IRB for more command line options.

 
               # File irb/context.rb, line 368
def debug_level=(value)
  @debug_level = value
  RubyLex.debug_level = value
end
            
eval_history=(no)

Sets command result history limit.

no is an Integer or nil.

Returns no of history items if greater than 0.

If no is 0, the number of history items is unlimited.

If no is nil, execution result history isn’t used (default).

 
               # File irb/ext/history.rb, line 44
def eval_history=(no)
  if no
    if defined?(@eval_history) && @eval_history
      @eval_history_values.size(no)
    else
      @eval_history_values = History.new(no)
      IRB.conf[:__TMP__EHV__] = @eval_history_values
      @workspace.evaluate(self, "__ = IRB.conf[:__TMP__EHV__]")
      IRB.conf.delete(:__TMP_EHV__)
    end
  else
    @eval_history_values = nil
  end
  @eval_history = no
end
            
exit(ret = 0)

Exits the current session, see IRB.irb_exit

 
               # File irb/context.rb, line 389
def exit(ret = 0)
  IRB.irb_exit(@irb, ret)
end
            
Also aliased as: __exit__
file_input?()

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

 
               # File irb/context.rb, line 292
def file_input?
  @io.class == FileInputMethod
end
            
history_file()

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

 
               # File irb/ext/save-history.rb, line 50
def history_file
  IRB.conf[:HISTORY_FILE]
end
            
history_file=(hist)

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

 
               # File irb/ext/save-history.rb, line 55
def history_file=(hist)
  IRB.conf[:HISTORY_FILE] = hist
end
            
home_workspace()

Inherited from TOPLEVEL_BINDING.

 
               # File irb/ext/change-ws.rb, line 17
def home_workspace
  if defined? @home_workspace
    @home_workspace
  else
    @home_workspace = @workspace
  end
end
            
inspect?()

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

 
               # File irb/context.rb, line 286
def inspect?
  @inspect_mode.nil? or @inspect_mode
end
            
inspect_mode=(opt)

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.

See Command line options at IRB for more command line options.

 
               # File irb/context.rb, line 309
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_level()

Size of the current WorkSpace stack

 
               # File irb/ext/workspaces.rb, line 17
def irb_level
  workspace_stack.size
end
            
main()

The top-level workspace, see IRB::WorkSpace#main

 
               # File irb/context.rb, line 107
def main
  @workspace.main
end
            
math_mode=(opt)

Sets bc mode, which loads lib/mathn.rb so fractions or matrix are available.

Also available as the -m command line option.

See Command line options at IRB and the unix manpage bc(1) for more information.

 
               # File irb/ext/math-mode.rb, line 30
def math_mode=(opt)
  if @math_mode == true && !opt
    IRB.fail CantReturnToNormalMode
    return
  end

  @math_mode = opt
  if math_mode
    main.extend Math
    print "start math mode\n" if verbose?
  end
end
            
pop_workspace()

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 58
def pop_workspace
  if workspaces.empty?
    print "workspace stack empty\n"
    return
  end
  @workspace = workspaces.pop
end
            
prompt_mode=(mode)

Sets the mode of the prompt in this context.

See Customizing the IRB Prompt at IRB for more information.

 
               # File irb/context.rb, line 270
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]
  @prompt_n = pconf[:PROMPT_N]
  @return_format = pconf[:RETURN]
  if ai = pconf.include?(:AUTO_INDENT)
    @auto_indent_mode = ai
  else
    @auto_indent_mode = IRB.conf[:AUTO_INDENT]
  end
end
            
prompting?()

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

 
               # File irb/context.rb, line 252
def prompting?
  verbose? || (STDIN.tty? && @io.kind_of?(StdioInputMethod) ||
               (defined?(ReadlineInputMethod) && @io.kind_of?(ReadlineInputMethod)))
end
            
push_workspace(*_main)

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

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

 
               # File irb/ext/workspaces.rb, line 35
def push_workspace(*_main)
  if _main.empty?
    if workspaces.empty?
      print "No other workspace\n"
      return nil
    end
    ws = workspaces.pop
    workspaces.push @workspace
    @workspace = ws
    return workspaces
  end

  workspaces.push @workspace
  @workspace = WorkSpace.new(@workspace.binding, _main[0])
  if !(class<<main;ancestors;end).include?(ExtendCommandBundle)
    main.extend ExtendCommandBundle
  end
end
            
save_history()

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

 
               # File irb/ext/save-history.rb, line 26
def save_history
  IRB.conf[:SAVE_HISTORY]
end
            
save_history=(val)

Sets IRB.conf[:SAVE_HISTORY] to the given val and calls init_save_history with this context.

Will store the number of val entries of history in the history_file

Add the following to your .irbrc to change the number of history entries stored to 1000:

IRB.conf[:SAVE_HISTORY] = 1000
 
               # File irb/ext/save-history.rb, line 40
def save_history=(val)
  IRB.conf[:SAVE_HISTORY] = val
  if val
    main_context = IRB.conf[:MAIN_CONTEXT]
    main_context = self unless main_context
    main_context.init_save_history
  end
end
            
set_last_value(value)

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

 
               # File irb/context.rb, line 262
def set_last_value(value)
  @last_value = value
  @workspace.evaluate self, "_ = IRB.CurrentContext.last_value"
end
            
Also aliased as: _set_last_value
use_loader()

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 41
def use_loader
  IRB.conf[:USE_LOADER]
end
            
Also aliased as: use_loader?
use_loader=(opt)

Sets IRB.conf

See use_loader for more information.

 
               # File irb/ext/use-loader.rb, line 50
def use_loader=(opt)

  if IRB.conf[:USE_LOADER] != opt
    IRB.conf[:USE_LOADER] = opt
    if opt
      if !$".include?("irb/cmd/load")
      end
      (class<<@workspace.main;self;end).instance_eval {
        alias_method :load, :irb_load
        alias_method :require, :irb_require
      }
    else
      (class<<@workspace.main;self;end).instance_eval {
        alias_method :load, :__original__load__IRB_use_loader__
        alias_method :require, :__original__require__IRB_use_loader__
      }
    end
  end
  print "Switch to load/require#{unless use_loader; ' non';end} trace mode.\n" if verbose?
  opt
end
            
use_loader?()
Alias for: use_loader
use_readline=(opt)

Obsolete method.

Can be set using the --noreadline and --readline command line options.

See Command line options at IRB for more command line options.

 
               # File irb/context.rb, line 358
def use_readline=(opt)
  print "This method is obsolete."
  print "Do nothing."
end
            
use_tracer=(opt)

Sets whether or not to use the Tracer library when evaluating statements in this context.

See lib/tracer.rb for more information.

 
               # File irb/ext/tracer.rb, line 37
def use_tracer=(opt)
  if opt
    Tracer.set_get_line_procs(@irb_path) {
      |line_no, *rests|
      @io.line(line_no)
    }
  elsif !opt && @use_tracer
    Tracer.off
  end
  @use_tracer=opt
end
            
verbose?()

Returns whether messages are displayed or not.

 
               # File irb/context.rb, line 236
def verbose?
  if @verbose.nil?
    if defined?(ReadlineInputMethod) && @io.kind_of?(ReadlineInputMethod)
      false
    elsif !STDIN.tty? or @io.kind_of?(FileInputMethod)
      true
    else
      false
    end
  else
    @verbose
  end
end
            
workspaces()

WorkSpaces in the current stack

 
               # File irb/ext/workspaces.rb, line 22
def workspaces
  if defined? @workspaces
    @workspaces
  else
    @workspaces = []
  end
end