# File lib/rake.rb, line 2045
2045:     def do_option(opt, value)
2046:       case opt
2047:       when '--describe'
2048:         options.show_tasks = true
2049:         options.show_task_pattern = Regexp.new(value || '.')
2050:         options.full_description = true
2051:       when '--dry-run'
2052:         verbose(true)
2053:         nowrite(true)
2054:         options.dryrun = true
2055:         options.trace = true
2056:       when '--help'
2057:         help
2058:         exit
2059:       when '--libdir'
2060:         $:.push(value)
2061:       when '--nosearch'
2062:         options.nosearch = true
2063:       when '--prereqs'
2064:         options.show_prereqs = true
2065:       when '--quiet'
2066:         verbose(false)
2067:       when '--rakefile'
2068:         @rakefiles.clear
2069:         @rakefiles << value
2070:       when '--rakelibdir'
2071:         options.rakelib = value.split(':')
2072:       when '--require'
2073:         begin
2074:           require value
2075:         rescue LoadError => ex
2076:           begin
2077:             rake_require value
2078:           rescue LoadError => ex2
2079:             raise ex
2080:           end
2081:         end
2082:       when '--silent'
2083:         verbose(false)
2084:         options.silent = true
2085:       when '--tasks'
2086:         options.show_tasks = true
2087:         options.show_task_pattern = Regexp.new(value || '.')
2088:         options.full_description = false
2089:       when '--trace'
2090:         options.trace = true
2091:         verbose(true)
2092:       when '--verbose'
2093:         verbose(true)
2094:       when '--version'
2095:         puts "rake, version #{RAKEVERSION}"
2096:         exit
2097:       when '--classic-namespace'
2098:         require 'rake/classic_namespace'
2099:         options.classic_namespace = true
2100:       end
2101:     end