_=%w'twen thir fo%sr fif six seven eigh nine'
puts:zero,b=%w'one two three four five six seven eight nine ten eleven twelve','%steen
'*7%_[1..7]%:u,_.map{|_|_=_%p+'ty';_+"
#{_} %s"*9%b},'one hundred'
Note that non-ascii characters in the above source code will be escaped (such as \x9f).