class IRB::ExtendCommand::IrbInfo

def execute
  str  = "Ruby version: #{RUBY_VERSION}\n"
  str += "IRB version: #{IRB.version}\n"
  str += "InputMethod: #{IRB.CurrentContext.io.inspect}\n"
  str += ".irbrc path: #{IRB.rc_file}\n" if File.exist?(IRB.rc_file)
  str += "RUBY_PLATFORM: #{RUBY_PLATFORM}\n"
  str += "LANG env: #{ENV["LANG"]}\n" if ENV["LANG"] && !ENV["LANG"].empty?
  str += "LC_ALL env: #{ENV["LC_ALL"]}\n" if ENV["LC_ALL"] && !ENV["LC_ALL"].empty?
  str += "East Asian Ambiguous Width: #{Reline.ambiguous_width.inspect}\n"
  if RbConfig::CONFIG['host_os'] =~ /mswin|msys|mingw|cygwin|bccwin|wince|emc/
    codepage = `chcp`.b.sub(/.*: (\d+)\n/, '\1')
    str += "Code page: #{codepage}\n"
  end
  puts str
  nil
end