Fun with directory recursion and Python

dirrec.py

fix = lambda f: lambda x: f(fix(f), x)


# presume Python's obsession with iterators...

join = __import__('itertools').chain.from_iterable
bind = lambda f, xs: join(map(f, xs))


# I/O primitives...

(subpaths, subdirs) = (lambda os: (
    lambda path: [os.path.join(path, x) for x in os.listdir(path)],
    lambda path: [x for x in subpaths(path) if os.path.isdir(x)],
))(__import__('os'))


# subdirs of subdirs...

step_subdirs = lambda f, dirs: dirs and dirs + f(list(bind(subdirs, dirs)))
recurse_subdirs = fix(step_subdirs)