do_option (Rake::Application)

          # File lib/rake.rb, line 1725
    1725:     def do_option(opt, value)
    1726:       case opt
    1727:       when '--dry-run'
    1728:         verbose(true)
    1729:         nowrite(true)
    1730:         options.dryrun = true
    1731:         options.trace = true
    1732:       when '--help'
    1733:         help
    1734:         exit
    1735:       when '--libdir'
    1736:         $:.push(value)
    1737:       when '--nosearch'
    1738:         options.nosearch = true
    1739:       when '--prereqs'
    1740:         options.show_prereqs = true
    1741:       when '--quiet'
    1742:         verbose(false)
    1743:       when '--rakefile'
    1744:         RAKEFILES.clear
    1745:         RAKEFILES << value
    1746:       when '--rakelibdir'
    1747:         options.rakelib = value.split(':')
    1748:       when '--require'
    1749:         begin
    1750:           require value
    1751:         rescue LoadError => ex
    1752:           begin
    1753:             rake_require value
    1754:           rescue LoadError => ex2
    1755:             raise ex
    1756:           end
    1757:         end
    1758:       when '--silent'
    1759:         verbose(false)
    1760:         options.silent = true
    1761:       when '--tasks'
    1762:         options.show_tasks = true
    1763:         options.show_task_pattern = Regexp.new(value || '.')
    1764:       when '--trace'
    1765:         options.trace = true
    1766:         verbose(true)
    1767:       when '--usage'
    1768:         usage
    1769:         exit
    1770:       when '--verbose'
    1771:         verbose(true)
    1772:       when '--version'
    1773:         puts "rake, version #{RAKEVERSION}"
    1774:         exit
    1775:       when '--classic-namespace'
    1776:         require 'rake/classic_namespace'
    1777:         options.classic_namespace = true
    1778:       else
    1779:         fail "Unknown option: #{opt}"
    1780:       end
    1781:     end