cython

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# mode: run
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# tag: sequence_unpacking
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import cython
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def _it(N):
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    for i in range(N):
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        yield i
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cdef class ItCount(object):
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    cdef object values
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    cdef readonly count
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    def __init__(self, values):
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        self.values = iter(values)
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        self.count = 0
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    def __iter__(self):
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        return self
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    def __next__(self):
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        self.count += 1
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        return next(self.values)
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def kunterbunt(obj1, obj2, obj3, obj4, obj5):
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    """
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    >>> kunterbunt(1, (2,), (3,4,5), (6,(7,(8,9))), 0)
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    (8, 9, (8, 9), (6, (7, (8, 9))), 0)
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    """
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    obj1, = obj2
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    obj1, obj2 = obj2 + obj2
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    obj1, obj2, obj3 = obj3
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    obj1, (obj2, obj3) = obj4
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    [obj1, obj2] = obj3
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    return obj1, obj2, obj3, obj4, obj5
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def unpack_tuple(tuple it):
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    """
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    >>> unpack_tuple((1,2,3))
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    (1, 2, 3)
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    >>> a,b,c = None   # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    TypeError: ...
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    >>> unpack_tuple(None)   # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    TypeError: ...
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    """
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    a,b,c = it
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    return a,b,c
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def unpack_list(list it):
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    """
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    >>> unpack_list([1,2,3])
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    (1, 2, 3)
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    >>> a,b,c = None   # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    TypeError: ...
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    >>> unpack_list(None)   # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    TypeError: ...
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    """
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    a,b,c = it
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    return a,b,c
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def unpack_to_itself(it):
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    """
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    >>> it = _it(2)
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    >>> it, it = it
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    >>> it
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    1
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    >>> unpack_to_itself([1,2])
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    2
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    >>> unpack_to_itself((1,2))
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    2
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    >>> unpack_to_itself(_it(2))
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    1
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    >>> unpack_to_itself((1,2,3))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 2)
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    >>> unpack_to_itself(_it(3))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 2)
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    """
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    it, it = it
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    return it
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def unpack_partial(it):
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    """
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    >>> it = _it(2)
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    >>> a = b = c = 0
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    >>> try: a,b,c = it
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    ... except ValueError: pass
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    ... else: print("DID NOT FAIL!")
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    >>> a, b, c
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    (0, 0, 0)
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    >>> unpack_partial([1,2])
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    (0, 0, 0)
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    >>> unpack_partial((1,2))
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    (0, 0, 0)
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    >>> unpack_partial(_it(2))
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    (0, 0, 0)
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    >>> it = ItCount([1,2])
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    >>> a = b = c = 0
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    >>> try: a,b,c = it
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    ... except ValueError: pass
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    ... else: print("DID NOT FAIL!")
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    >>> a, b, c
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    (0, 0, 0)
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    >>> it.count
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    3
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    >>> it = ItCount([1,2])
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    >>> unpack_partial(it)
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    (0, 0, 0)
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    >>> it.count
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    3
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    """
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    a = b = c = 0
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    try:
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        a, b, c = it
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    except ValueError:
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        pass
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    return a, b, c
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def unpack_fail_assignment(it):
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    """
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    >>> it = ItCount([1, 2, 3])
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    >>> a = b = c = 0
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    >>> try: a, b[0], c = it
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    ... except TypeError: pass
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    >>> a,b,c
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    (1, 0, 0)
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    >>> it.count
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    4
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    >>> it = ItCount([1, 2, 3])
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    >>> unpack_fail_assignment(it)
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    (1, 0, 0)
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    >>> it.count
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    4
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    """
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    cdef object a,b,c
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    a = b = c = 0
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    try:
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        a, b[0], c = it
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    except TypeError:
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        pass
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    return a, b, c
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def unpack_partial_typed(it):
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    """
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    >>> unpack_partial_typed([1, 2, 'abc'])
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    (0, 0, 0)
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    >>> unpack_partial_typed((1, 'abc', 3))
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    (0, 0, 0)
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    >>> unpack_partial_typed(set([1, 'abc', 3]))
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    (0, 0, 0)
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    >>> it = ItCount([1, 'abc', 3])
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    >>> unpack_partial_typed(it)
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    (0, 0, 0)
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    >>> it.count
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    4
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    """
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    cdef int a,b,c
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    a = b = c = 0
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    try:
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        a, b, c = it
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    except TypeError:
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        pass
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    return a, b, c
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def unpack_typed(it):
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    """
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    >>> unpack_typed((1, 2.0, [1]))
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    (1, 2.0, [1])
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    >>> unpack_typed([1, 2.0, [1]])
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    (1, 2.0, [1])
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    >>> it = ItCount([1, 2.0, [1]])
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    >>> unpack_typed(it)
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    (1, 2.0, [1])
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    >>> it.count
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    4
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    >>> try: unpack_typed((1, None, [1]))
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    ... except TypeError: pass
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    >>> try: unpack_typed([1, None, [1]])
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    ... except TypeError: pass
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    >>> it = ItCount([1, None, [1]])
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    >>> try: unpack_typed(it)
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    ... except TypeError: pass
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    >>> it.count
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    4
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    >>> unpack_typed((1, 2.0, (1,)))
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    Traceback (most recent call last):
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    TypeError: Expected list, got tuple
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    >>> it = ItCount([1, 2.0, (1,)])
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    >>> unpack_typed(it)
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    Traceback (most recent call last):
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    TypeError: Expected list, got tuple
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    >>> it.count
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    4
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    """
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    cdef int a
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    cdef float b
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    cdef list c
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    a,b,c = it
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    return a,b,c
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def failure_too_many(it):
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    """
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    >>> try: a,b,c = [1,2,3,4]
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    ... except ValueError: pass
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    >>> failure_too_many([1,2,3,4])
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 3)
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    >>> try: a,b,c = [1,2,3,4]
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    ... except ValueError: pass
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    >>> failure_too_many((1,2,3,4))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 3)
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    >>> a,b,c = set([1,2,3,4])    # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    ValueError: too many values to unpack...
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    >>> failure_too_many(set([1,2,3,4]))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 3)
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    >>> a,b,c = _it(4)    # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    ValueError: too many values to unpack...
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    >>> failure_too_many(_it(4))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 3)
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    """
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    a,b,c = it
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    return a,b,c
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def failure_too_few(it):
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    """
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    >>> try: a,b,c = [1,2]
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    ... except ValueError: pass
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    >>> failure_too_few([1,2])
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    Traceback (most recent call last):
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    ValueError: need more than 2 values to unpack
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    >>> try: a,b,c = (1,2)
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    ... except ValueError: pass
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    >>> failure_too_few((1,2))
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    Traceback (most recent call last):
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    ValueError: need more than 2 values to unpack
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    >>> try: a,b,c = set([1,2])
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    ... except ValueError: pass
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    ... else: print("DID NOT FAIL!")
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    >>> failure_too_few(set([1,2]))
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    Traceback (most recent call last):
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    ValueError: need more than 2 values to unpack
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    >>> try: a,b,c = _it(2)
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    ... except ValueError: pass
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    ... else: print("DID NOT FAIL!")
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    >>> failure_too_few(_it(2))
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    Traceback (most recent call last):
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    ValueError: need more than 2 values to unpack
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    """
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    a,b,c = it
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    return a,b,c
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def _it_failure(N):
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    for i in range(N):
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        yield i
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    raise ValueError("huhu")
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def failure_while_unpacking(it):
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    """
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    >>> a,b,c = _it_failure(0)
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> failure_while_unpacking(_it_failure(0))
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> a,b,c = _it_failure(1)
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> failure_while_unpacking(_it_failure(1))
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> a,b,c = _it_failure(2)
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> failure_while_unpacking(_it_failure(2))
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> a,b,c = _it_failure(3)
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> failure_while_unpacking(_it_failure(3))
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    Traceback (most recent call last):
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    ValueError: huhu
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    >>> a,b,c = _it_failure(4)    # doctest: +ELLIPSIS
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    Traceback (most recent call last):
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    ValueError: too many values to unpack...
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    >>> failure_while_unpacking(_it_failure(4))
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    Traceback (most recent call last):
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    ValueError: too many values to unpack (expected 3)
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    """
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    a,b,c = it
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    return a,b,c
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def unpack_many(it):
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    """
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    >>> items = range(1,13)
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    >>> unpack_many(items)
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many(iter(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many(list(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many(tuple(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    """
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    a,b,c,d,e,f,g,h,i,j,k,l = it
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    return a,b,c,d,e,f,g,h,i,j,k,l
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def unpack_many_tuple(tuple it):
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    """
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    >>> items = range(1,13)
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    >>> unpack_many_tuple(tuple(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    """
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    a,b,c,d,e,f,g,h,i,j,k,l = it
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    return a,b,c,d,e,f,g,h,i,j,k,l
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def unpack_many_list(list it):
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    """
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    >>> items = range(1,13)
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    >>> unpack_many_list(list(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    """
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    a,b,c,d,e,f,g,h,i,j,k,l = it
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    return a,b,c,d,e,f,g,h,i,j,k,l
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def unpack_many_int(it):
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    """
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    >>> items = range(1,13)
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    >>> unpack_many_int(items)
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many_int(iter(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many_int(list(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    >>> unpack_many_int(tuple(items))
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    (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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    """
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    cdef int b
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    cdef long f
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    cdef Py_ssize_t h
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    a,b,c,d,e,f,g,h,i,j,k,l = it
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    return a,b,c,d,e,f,g,h,i,j,k,l
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@cython.test_fail_if_path_exists('//PyTypeTestNode')
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def unpack_literal_none_to_builtin_type():
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    """
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    >>> unpack_literal_none_to_builtin_type()
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    (None, None, None, None)
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    """
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    cdef list a,b,c,d
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    a, b = c, d = None, None
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    return a,b,c,d
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382

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cdef class ExtType:
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    pass
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386

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@cython.test_fail_if_path_exists('//PyTypeTestNode')
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def unpack_literal_none_to_exttype():
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    """
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    >>> unpack_literal_none_to_exttype()
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    (None, None, None, None)
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    """
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    cdef ExtType a,b,c,d
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    a, b = c, d = None, None
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    return a,b,c,d
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397

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# Github issue #1523
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def test_unpack_resultref():
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    """
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    >>> test_unpack_resultref() == ((1, set()), 1, set())
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    True
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    """
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    a = b, c = 1, set()
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    return a, b, c
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