cython

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# mode: run
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def typename(t):
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    name = type(t).__name__
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    return "<type '%s'>" % name
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class MyException(Exception):
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    pass
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class ContextManager(object):
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    def __init__(self, value, exit_ret = None):
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        self.value = value
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        self.exit_ret = exit_ret
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    def __exit__(self, a, b, tb):
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        print("exit %s %s %s" % (typename(a), typename(b), typename(tb)))
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        return self.exit_ret
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    def __enter__(self):
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        print("enter")
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        return self.value
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def no_as():
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    """
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    >>> no_as()
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    enter
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    hello
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with ContextManager("value"):
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        print("hello")
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def basic():
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    """
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    >>> basic()
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    enter
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    value
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with ContextManager("value") as x:
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        print(x)
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def with_pass():
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    """
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    >>> with_pass()
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with ContextManager("value") as x:
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        pass
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def with_return():
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    """
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    >>> print(with_return())
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    value
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    """
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    with ContextManager("value") as x:
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        return x
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def with_break():
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    """
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    >>> print(with_break())
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    a
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    """
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    for c in list("abc"):
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        with ContextManager("value") as x:
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            break
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        print("FAILED")
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    return c
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def with_continue():
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    """
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    >>> print(with_continue())
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    enter
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    c
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    """
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    for c in list("abc"):
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        with ContextManager("value") as x:
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            continue
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        print("FAILED")
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    return c
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def with_exception(exit_ret):
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    """
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    >>> with_exception(None)
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    enter
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    value
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    exit <type 'type'> <type 'MyException'> <type 'traceback'>
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    outer except
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    >>> with_exception(True)
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    enter
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    value
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    exit <type 'type'> <type 'MyException'> <type 'traceback'>
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    """
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    try:
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        with ContextManager("value", exit_ret=exit_ret) as value:
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            print(value)
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            raise MyException()
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    except:
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        print("outer except")
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def with_real_lock():
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    """
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    >>> with_real_lock()
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    about to acquire lock
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    holding lock
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    lock no longer held
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    """
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    from threading import Lock
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    lock = Lock()
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    print("about to acquire lock")
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    with lock:
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        print("holding lock")
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    print("lock no longer held")
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def functions_in_with():
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    """
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    >>> f = functions_in_with()
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    enter
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    exit <type 'type'> <type 'MyException'> <type 'traceback'>
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    outer except
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    >>> f(1)[0]
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    1
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    >>> print(f(1)[1])
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    value
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    """
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    try:
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        with ContextManager("value") as value:
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            def f(x): return x, value
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            make = lambda x:x()
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            raise make(MyException)
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    except:
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        print("outer except")
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    return f
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def multitarget():
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    """
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    >>> multitarget()
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    enter
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    1 2 3 4 5
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with ContextManager((1, 2, (3, (4, 5)))) as (a, b, (c, (d, e))):
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        print('%s %s %s %s %s' % (a, b, c, d, e))
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def tupletarget():
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    """
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    >>> tupletarget()
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    enter
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    (1, 2, (3, (4, 5)))
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with ContextManager((1, 2, (3, (4, 5)))) as t:
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        print(t)
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class GetManager(object):
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    def get(self, *args):
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        return ContextManager(*args)
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def manager_from_expression():
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    """
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    >>> manager_from_expression()
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    enter
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    1
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    enter
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    2
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    exit <type 'NoneType'> <type 'NoneType'> <type 'NoneType'>
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    """
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    with GetManager().get(1) as x:
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        print(x)
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    g = GetManager()
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    with g.get(2) as x:
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        print(x)
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def manager_from_ternary(use_first):
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    """
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    >>> manager_from_ternary(True)
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    enter
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    exit <type 'type'> <type 'ValueError'> <type 'traceback'>
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    >>> manager_from_ternary(False)
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    enter
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    exit <type 'type'> <type 'ValueError'> <type 'traceback'>
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    In except
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    """
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    # This is mostly testing a parsing problem, hence the
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    # result of the ternary must be callable
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    cm1_getter = lambda: ContextManager("1", exit_ret=True)
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    cm2_getter = lambda: ContextManager("2")
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    try:
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        with (cm1_getter if use_first else cm2_getter)():
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            raise ValueError
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    except ValueError:
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        print("In except")
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