Beta Shell v2.0

File Manager

Name	Size	Perms	Modified	Actions
[ .. / .. ]
LICENSE.txt	12.48 KB	-rw-r--r--	2022-02-22 15:51:05	Edit Del
__future__.py	4.73 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
__phello__.foo.py	64 B	-rw-r--r--	2022-02-22 15:51:01	Edit Del
__pycache__	-	drwxr-xr-x	2022-02-22 15:51:24	Del
_bootlocale.py	1.27 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_collections_abc.py	24.21 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_compat_pickle.py	8.36 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_compression.py	5.21 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_dummy_thread.py	5 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_markupbase.py	14.26 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
_osx_support.py	18.67 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_pydecimal.py	223.27 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_pyio.py	85.91 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_sitebuiltins.py	3.04 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_strptime.py	21.67 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_sysconfigdata.py	18.17 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_threading_local.py	7.24 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
_weakrefset.py	5.57 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
abc.py	8.43 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
aifc.py	31.22 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
antigravity.py	476 B	-rw-r--r--	2022-02-22 15:51:00	Edit Del
argparse.py	88.03 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
ast.py	11.72 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
asynchat.py	11.69 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
asyncio	-	drwxr-xr-x	2022-02-22 15:51:05	Del
asyncore.py	19.63 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
base64.py	20.03 KB	-rwxr-xr-x	2022-02-22 15:51:00	Edit Del
bdb.py	22.81 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
binhex.py	13.63 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
bisect.py	2.53 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
bz2.py	12.13 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
cProfile.py	5.19 KB	-rwxr-xr-x	2022-02-22 15:51:00	Edit Del
calendar.py	22.46 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
cgi.py	35.19 KB	-rwxr-xr-x	2022-02-22 15:51:00	Edit Del
cgitb.py	11.74 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
chunk.py	5.3 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
cmd.py	14.51 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
code.py	9.88 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
codecs.py	35.38 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
codeop.py	5.85 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
collections	-	drwxr-xr-x	2022-02-22 15:51:05	Del
colorsys.py	3.97 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
compileall.py	11.44 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
concurrent	-	drwxr-xr-x	2022-02-22 15:51:05	Del
config-3.5m	-	drwxr-xr-x	2022-02-22 15:51:25	Del
configparser.py	52.2 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
contextlib.py	12.16 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
copy.py	8.74 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
copyreg.py	6.67 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
crypt.py	1.83 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
csv.py	15.75 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
ctypes	-	drwxr-xr-x	2022-02-22 15:51:06	Del
curses	-	drwxr-xr-x	2022-02-22 15:51:06	Del
datetime.py	74.12 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
dbm	-	drwxr-xr-x	2022-02-22 15:51:06	Del
decimal.py	320 B	-rw-r--r--	2022-02-22 15:51:00	Edit Del
difflib.py	82.23 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
dis.py	16.94 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
distutils	-	drwxr-xr-x	2022-02-22 15:51:06	Del
doctest.py	101.6 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
dummy_threading.py	2.75 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
email	-	drwxr-xr-x	2022-02-22 15:51:06	Del
encodings	-	drwxr-xr-x	2022-02-22 15:51:06	Del
ensurepip	-	drwxr-xr-x	2022-02-22 15:51:06	Del
enum.py	21.71 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
filecmp.py	9.6 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
fileinput.py	13.92 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
fnmatch.py	3.09 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
formatter.py	14.79 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
fractions.py	24.04 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
ftplib.py	34.13 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
functools.py	28.27 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
genericpath.py	4.26 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
getopt.py	7.31 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
getpass.py	5.85 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
gettext.py	21.03 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
glob.py	4.95 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
gzip.py	19.79 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
hashlib.py	7.79 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
heapq.py	22.39 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
hmac.py	4.94 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
html	-	drwxr-xr-x	2022-02-22 15:51:06	Del
http	-	drwxr-xr-x	2022-02-22 15:51:06	Del
idlelib	-	drwxr-xr-x	2022-02-22 15:51:06	Del
imaplib.py	50.96 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
imghdr.py	3.67 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
imp.py	10.43 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
importlib	-	drwxr-xr-x	2022-02-22 15:51:05	Del
inspect.py	111.52 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
io.py	3.32 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
ipaddress.py	73.97 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
json	-	drwxr-xr-x	2022-02-22 15:51:07	Del
keyword.py	2.16 KB	-rwxr-xr-x	2022-02-22 15:51:00	Edit Del
lib-dynload	-	drwxr-xr-x	2022-02-22 15:51:26	Del
lib2to3	-	drwxr-xr-x	2022-02-22 15:51:25	Del
linecache.py	5.19 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
locale.py	72.96 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
logging	-	drwxr-xr-x	2022-02-22 15:51:05	Del
lzma.py	12.62 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
macpath.py	5.77 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
macurl2path.py	2.67 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
mailbox.py	76.58 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
mailcap.py	7.91 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
mimetypes.py	20.36 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
modulefinder.py	22.54 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
multiprocessing	-	drwxr-xr-x	2022-02-22 15:51:05	Del
netrc.py	5.61 KB	-rw-r--r--	2022-02-22 15:51:00	Edit Del
nntplib.py	42.07 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
ntpath.py	22.26 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
nturl2path.py	2.39 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
numbers.py	10 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
opcode.py	5.75 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
operator.py	10.61 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
optparse.py	58.93 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
os.py	36.17 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pathlib.py	45.9 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pdb.py	59.71 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
pickle.py	54.86 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pickletools.py	89.61 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pipes.py	8.71 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pkgutil.py	20.85 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
plat-linux	-	drwxr-xr-x	2022-02-22 15:51:07	Del
platform.py	45.05 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
plistlib.py	31.06 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
poplib.py	14.37 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
posixpath.py	14.56 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pprint.py	20.37 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
profile.py	21.5 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
pstats.py	25.94 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pty.py	4.65 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
py_compile.py	7.01 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pyclbr.py	13.25 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
pydoc.py	101.21 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
pydoc_data	-	drwxr-xr-x	2022-02-22 15:51:07	Del
queue.py	8.57 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
quopri.py	7.08 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
random.py	25.84 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
re.py	15.14 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
reprlib.py	5.21 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
rlcompleter.py	6.16 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
runpy.py	11.68 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sched.py	6.07 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
selectors.py	18.98 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
shelve.py	8.33 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
shlex.py	11.18 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
shutil.py	39.11 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
signal.py	2.07 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
site-packages	-	drwxr-xr-x	2023-02-03 07:35:44	Del
site.py	20.74 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
smtpd.py	34.53 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
smtplib.py	42.6 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
sndhdr.py	6.27 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
socket.py	26.5 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
socketserver.py	24.09 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sqlite3	-	drwxr-xr-x	2022-02-22 15:51:07	Del
sre_compile.py	17.98 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sre_constants.py	6.66 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sre_parse.py	34.29 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
ssl.py	41.36 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
stat.py	4.92 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
statistics.py	19.08 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
string.py	11.58 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
stringprep.py	12.61 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
struct.py	257 B	-rw-r--r--	2022-02-22 15:51:01	Edit Del
subprocess.py	57.53 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sunau.py	17.67 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
symbol.py	2.05 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
symtable.py	7.02 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
sysconfig.py	23.77 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
tabnanny.py	11.14 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
tarfile.py	90.96 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
telnetlib.py	22.48 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
tempfile.py	26.01 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
test	-	drwxr-xr-x	2022-02-22 15:51:07	Del
textwrap.py	19.1 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
this.py	1003 B	-rw-r--r--	2022-02-22 15:51:01	Edit Del
threading.py	47.88 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
timeit.py	12.1 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
tkinter	-	drwxr-xr-x	2022-02-22 15:51:11	Del
token.py	3 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
tokenize.py	27.14 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
trace.py	30.8 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
traceback.py	21.66 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
tracemalloc.py	15.27 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
tty.py	879 B	-rw-r--r--	2022-02-22 15:51:01	Edit Del
turtle.py	140.25 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
turtledemo	-	drwxr-xr-x	2022-02-22 15:51:11	Del
types.py	8.59 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
typing.py	78.26 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
unittest	-	drwxr-xr-x	2022-02-22 15:51:11	Del
urllib	-	drwxr-xr-x	2022-02-22 15:51:11	Del
uu.py	6.74 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
uuid.py	22.72 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
venv	-	drwxr-xr-x	2022-02-22 15:51:11	Del
warnings.py	15.48 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
wave.py	17.27 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
weakref.py	19.99 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
webbrowser.py	21.31 KB	-rwxr-xr-x	2022-02-22 15:51:01	Edit Del
wsgiref	-	drwxr-xr-x	2022-02-22 15:51:11	Del
xdrlib.py	5.77 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
xml	-	drwxr-xr-x	2022-02-22 15:51:11	Del
xmlrpc	-	drwxr-xr-x	2022-02-22 15:51:11	Del
zipapp.py	6.99 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del
zipfile.py	71.95 KB	-rw-r--r--	2022-02-22 15:51:01	Edit Del

Editing: contextlib.py (12.16 KB)

"""Utilities for with-statement contexts.  See PEP 343."""

import sys
from collections import deque
from functools import wraps

__all__ = ["contextmanager", "closing", "ContextDecorator", "ExitStack",
           "redirect_stdout", "redirect_stderr", "suppress"]


class ContextDecorator(object):
    "A base class or mixin that enables context managers to work as decorators."

    def _recreate_cm(self):
        """Return a recreated instance of self.

        Allows an otherwise one-shot context manager like
        _GeneratorContextManager to support use as
        a decorator via implicit recreation.

        This is a private interface just for _GeneratorContextManager.
        See issue #11647 for details.
        """
        return self

    def __call__(self, func):
        @wraps(func)
        def inner(*args, **kwds):
            with self._recreate_cm():
                return func(*args, **kwds)
        return inner


class _GeneratorContextManager(ContextDecorator):
    """Helper for @contextmanager decorator."""

    def __init__(self, func, args, kwds):
        self.gen = func(*args, **kwds)
        self.func, self.args, self.kwds = func, args, kwds
        # Issue 19330: ensure context manager instances have good docstrings
        doc = getattr(func, "__doc__", None)
        if doc is None:
            doc = type(self).__doc__
        self.__doc__ = doc
        # Unfortunately, this still doesn't provide good help output when
        # inspecting the created context manager instances, since pydoc
        # currently bypasses the instance docstring and shows the docstring
        # for the class instead.
        # See http://bugs.python.org/issue19404 for more details.

    def _recreate_cm(self):
        # _GCM instances are one-shot context managers, so the
        # CM must be recreated each time a decorated function is
        # called
        return self.__class__(self.func, self.args, self.kwds)

    def __enter__(self):
        try:
            return next(self.gen)
        except StopIteration:
            raise RuntimeError("generator didn't yield") from None

    def __exit__(self, type, value, traceback):
        if type is None:
            try:
                next(self.gen)
            except StopIteration:
                return False
            else:
                raise RuntimeError("generator didn't stop")
        else:
            if value is None:
                # Need to force instantiation so we can reliably
                # tell if we get the same exception back
                value = type()
            try:
                self.gen.throw(type, value, traceback)
            except StopIteration as exc:
                # Suppress StopIteration *unless* it's the same exception that
                # was passed to throw().  This prevents a StopIteration
                # raised inside the "with" statement from being suppressed.
                return exc is not value
            except RuntimeError as exc:
                # Don't re-raise the passed in exception. (issue27122)
                if exc is value:
                    return False
                # Likewise, avoid suppressing if a StopIteration exception
                # was passed to throw() and later wrapped into a RuntimeError
                # (see PEP 479).
                if type is StopIteration and exc.__cause__ is value:
                    return False
                raise
            except:
                # only re-raise if it's *not* the exception that was
                # passed to throw(), because __exit__() must not raise
                # an exception unless __exit__() itself failed.  But throw()
                # has to raise the exception to signal propagation, so this
                # fixes the impedance mismatch between the throw() protocol
                # and the __exit__() protocol.
                #
                if sys.exc_info()[1] is value:
                    return False
                raise
            raise RuntimeError("generator didn't stop after throw()")


def contextmanager(func):
    """@contextmanager decorator.

    Typical usage:

        @contextmanager
        def some_generator(<arguments>):
            <setup>
            try:
                yield <value>
            finally:
                <cleanup>

    This makes this:

        with some_generator(<arguments>) as <variable>:
            <body>

    equivalent to this:

        <setup>
        try:
            <variable> = <value>
            <body>
        finally:
            <cleanup>

    """
    @wraps(func)
    def helper(*args, **kwds):
        return _GeneratorContextManager(func, args, kwds)
    return helper


class closing(object):
    """Context to automatically close something at the end of a block.

    Code like this:

        with closing(<module>.open(<arguments>)) as f:
            <block>

    is equivalent to this:

        f = <module>.open(<arguments>)
        try:
            <block>
        finally:
            f.close()

    """
    def __init__(self, thing):
        self.thing = thing
    def __enter__(self):
        return self.thing
    def __exit__(self, *exc_info):
        self.thing.close()


class _RedirectStream:

    _stream = None

    def __init__(self, new_target):
        self._new_target = new_target
        # We use a list of old targets to make this CM re-entrant
        self._old_targets = []

    def __enter__(self):
        self._old_targets.append(getattr(sys, self._stream))
        setattr(sys, self._stream, self._new_target)
        return self._new_target

    def __exit__(self, exctype, excinst, exctb):
        setattr(sys, self._stream, self._old_targets.pop())


class redirect_stdout(_RedirectStream):
    """Context manager for temporarily redirecting stdout to another file.

        # How to send help() to stderr
        with redirect_stdout(sys.stderr):
            help(dir)

        # How to write help() to a file
        with open('help.txt', 'w') as f:
            with redirect_stdout(f):
                help(pow)
    """

    _stream = "stdout"


class redirect_stderr(_RedirectStream):
    """Context manager for temporarily redirecting stderr to another file."""

    _stream = "stderr"


class suppress:
    """Context manager to suppress specified exceptions

    After the exception is suppressed, execution proceeds with the next
    statement following the with statement.

         with suppress(FileNotFoundError):
             os.remove(somefile)
         # Execution still resumes here if the file was already removed
    """

    def __init__(self, *exceptions):
        self._exceptions = exceptions

    def __enter__(self):
        pass

    def __exit__(self, exctype, excinst, exctb):
        # Unlike isinstance and issubclass, CPython exception handling
        # currently only looks at the concrete type hierarchy (ignoring
        # the instance and subclass checking hooks). While Guido considers
        # that a bug rather than a feature, it's a fairly hard one to fix
        # due to various internal implementation details. suppress provides
        # the simpler issubclass based semantics, rather than trying to
        # exactly reproduce the limitations of the CPython interpreter.
        #
        # See http://bugs.python.org/issue12029 for more details
        return exctype is not None and issubclass(exctype, self._exceptions)


# Inspired by discussions on http://bugs.python.org/issue13585
class ExitStack(object):
    """Context manager for dynamic management of a stack of exit callbacks

    For example:

        with ExitStack() as stack:
            files = [stack.enter_context(open(fname)) for fname in filenames]
            # All opened files will automatically be closed at the end of
            # the with statement, even if attempts to open files later
            # in the list raise an exception

    """
    def __init__(self):
        self._exit_callbacks = deque()

    def pop_all(self):
        """Preserve the context stack by transferring it to a new instance"""
        new_stack = type(self)()
        new_stack._exit_callbacks = self._exit_callbacks
        self._exit_callbacks = deque()
        return new_stack

    def _push_cm_exit(self, cm, cm_exit):
        """Helper to correctly register callbacks to __exit__ methods"""
        def _exit_wrapper(*exc_details):
            return cm_exit(cm, *exc_details)
        _exit_wrapper.__self__ = cm
        self.push(_exit_wrapper)

    def push(self, exit):
        """Registers a callback with the standard __exit__ method signature

        Can suppress exceptions the same way __exit__ methods can.

        Also accepts any object with an __exit__ method (registering a call
        to the method instead of the object itself)
        """
        # We use an unbound method rather than a bound method to follow
        # the standard lookup behaviour for special methods
        _cb_type = type(exit)
        try:
            exit_method = _cb_type.__exit__
        except AttributeError:
            # Not a context manager, so assume its a callable
            self._exit_callbacks.append(exit)
        else:
            self._push_cm_exit(exit, exit_method)
        return exit # Allow use as a decorator

    def callback(self, callback, *args, **kwds):
        """Registers an arbitrary callback and arguments.

        Cannot suppress exceptions.
        """
        def _exit_wrapper(exc_type, exc, tb):
            callback(*args, **kwds)
        # We changed the signature, so using @wraps is not appropriate, but
        # setting __wrapped__ may still help with introspection
        _exit_wrapper.__wrapped__ = callback
        self.push(_exit_wrapper)
        return callback # Allow use as a decorator

    def enter_context(self, cm):
        """Enters the supplied context manager

        If successful, also pushes its __exit__ method as a callback and
        returns the result of the __enter__ method.
        """
        # We look up the special methods on the type to match the with statement
        _cm_type = type(cm)
        _exit = _cm_type.__exit__
        result = _cm_type.__enter__(cm)
        self._push_cm_exit(cm, _exit)
        return result

    def close(self):
        """Immediately unwind the context stack"""
        self.__exit__(None, None, None)

    def __enter__(self):
        return self

    def __exit__(self, *exc_details):
        received_exc = exc_details[0] is not None

        # We manipulate the exception state so it behaves as though
        # we were actually nesting multiple with statements
        frame_exc = sys.exc_info()[1]
        def _fix_exception_context(new_exc, old_exc):
            # Context may not be correct, so find the end of the chain
            while 1:
                exc_context = new_exc.__context__
                if exc_context is old_exc:
                    # Context is already set correctly (see issue 20317)
                    return
                if exc_context is None or exc_context is frame_exc:
                    break
                new_exc = exc_context
            # Change the end of the chain to point to the exception
            # we expect it to reference
            new_exc.__context__ = old_exc

        # Callbacks are invoked in LIFO order to match the behaviour of
        # nested context managers
        suppressed_exc = False
        pending_raise = False
        while self._exit_callbacks:
            cb = self._exit_callbacks.pop()
            try:
                if cb(*exc_details):
                    suppressed_exc = True
                    pending_raise = False
                    exc_details = (None, None, None)
            except:
                new_exc_details = sys.exc_info()
                # simulate the stack of exceptions by setting the context
                _fix_exception_context(new_exc_details[1], exc_details[1])
                pending_raise = True
                exc_details = new_exc_details
        if pending_raise:
            try:
                # bare "raise exc_details[1]" replaces our carefully
                # set-up context
                fixed_ctx = exc_details[1].__context__
                raise exc_details[1]
            except BaseException:
                exc_details[1].__context__ = fixed_ctx
                raise
        return received_exc and suppressed_exc