cython

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# ticket: t258
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cdef extern from "Python.h":
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    ctypedef class __builtin__.list  [object PyListObject]:
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        cdef Py_ssize_t allocated
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    ctypedef class __builtin__.dict  [object PyDictObject]:
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        pass
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    cdef Py_ssize_t Py_SIZE(object o)
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cdef list L = [1,2,4]
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cdef dict d = {'A': 'a'}
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def test_list(list L):
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    """
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    >>> test_list(list(range(10)))
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    True
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    >>> class list_subclass(list): pass
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    >>> test_list(list_subclass([1,2,3]))
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    True
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    """
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    return Py_SIZE(L) <= L.allocated
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def test_tuple(tuple t):
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    """
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    Actual builtin types are restrictive wrt subclassing so optimizations can be safely performed.
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    >>> test_tuple((1,2))
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    2
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    >>> class tuple_subclass(tuple): pass
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    >>> test_tuple(tuple_subclass((1,2)))
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    Traceback (most recent call last):
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    ...
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    TypeError: Argument 't' has incorrect type (expected tuple, got tuple_subclass)
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    """
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    return len(t)
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