U:\trifork_projects\coroutines>ruby compare.rb
diffing first and second
<<<first/0.txt
>>>second/2.txt
    diffing first/A and second/A
        diffing first/A/AA and second/A/AA
        FINISHED diffing first/A/AA and second/A/AA
    >>>second/A/a0.txt
    <<<first/A/a1.txt
    FINISHED diffing first/A and second/A
<<<dir: first/B
    <<<dir: first/B/C
        <<<c1.txt
        <<<c2.txt
    <<<b1.txt
>>>dir: second/C
    >>>c1.txt
    >>>c2.txt
<<<dir: first/Z
FINISHED diffing first and second