Source code for complexity.utils
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
complexity.utils
----------------
Helper functions used throughout Complexity.
"""
import errno
import os
import sys
PY3 = sys.version > '3'
if PY3:
pass
else:
import codecs
input = raw_input
[docs]def make_sure_path_exists(path):
"""
Ensures that a directory exists.
:param path: A directory path.
"""
try:
os.makedirs(path)
except OSError as exception:
if exception.errno != errno.EEXIST:
return False
return True
[docs]def unicode_open(filename, *args, **kwargs):
"""
Opens a file as usual on Python 3, and with UTF-8 encoding on Python 2.
:param filename: Name of file to open.
"""
if PY3:
return open(filename, *args, **kwargs)
kwargs['encoding'] = "utf-8"
return codecs.open(filename, *args, **kwargs)
[docs]def query_yes_no(question, default="yes"):
"""
Ask a yes/no question via `raw_input()` and return their answer.
:param question: A string that is presented to the user.
:param default: The presumed answer if the user just hits <Enter>.
It must be "yes" (the default), "no" or None (meaning
an answer is required of the user).
The "answer" return value is one of "yes" or "no".
Adapted from
http://stackoverflow.com/questions/3041986/python-command-line-yes-no-input
http://code.activestate.com/recipes/577058/
"""
valid = {"yes": True, "y": True, "ye": True, "no": False, "n": False}
if default is None:
prompt = " [y/n] "
elif default == "yes":
prompt = " [Y/n] "
elif default == "no":
prompt = " [y/N] "
else:
raise ValueError("invalid default answer: '%s'" % default)
while True:
sys.stdout.write(question + prompt)
choice = input().lower()
if default is not None and choice == '':
return valid[default]
elif choice in valid:
return valid[choice]
else:
sys.stdout.write("Please respond with 'yes' or 'no' "
"(or 'y' or 'n').\n")