templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
import argparse
import os
ap = argparse.ArgumentParser()
ap.add_argument('path', nargs='+')
opts = ap.parse_args()
def gather():
for p in opts.path:
if not os.path.exists(p):
return
if os.path.isdir(p):
yield p + os.path.sep
for dirpath, dirs, files in os.walk(p):
for d in dirs:
yield os.path.join(dirpath, d) + os.path.sep
for f in files:
yield os.path.join(dirpath, f)
else:
yield p
print('\n'.join(sorted(gather(), key=lambda x: x.replace(os.path.sep, '/'))))