cimport cython

module_level_tuple = (1,2,3)

def return_module_level_tuple():

    """

    >>> return_module_level_tuple()

    (1, 2, 3)

    """

    return module_level_tuple

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_empty_tuple():

    """

    >>> return_empty_tuple()

    ()

    """

    return ()

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_constant_tuple1():

    """

    >>> return_constant_tuple1()

    (1,)

    """

    return (1,)

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_folded_tuple():

    """

    >>> return_folded_tuple()

    (1, 2, 3)

    """

    return (1, 1+1, 1+1+1)

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_nested_tuple():

    """

    >>> return_nested_tuple()

    (1, (2, 3), (3, (4, 5)))

    """

    return (1, (2, 3), (3, (4, 5)))

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def constant_tuple1():

    """

    >>> constant_tuple1()

    (1,)

    """

    tuple1 = (1,)

    return tuple1

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_constant_tuple2():

    """

    >>> return_constant_tuple2()

    (1, 2)

    """

    return (1,2)

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_constant_tuple_strings():

    """

    >>> return_constant_tuple_strings()

    ('tuple_1', 'bc', 'tuple_2')

    """

    return ('tuple_1', 'bc', 'tuple_2')

@cython.test_assert_path_exists("//TupleNode",

                                "//TupleNode[@is_literal = true]")

@cython.test_fail_if_path_exists("//TupleNode[@is_literal = false]")

def return_constant_tuples_string_types():

    """

    >>> a,b,c = return_constant_tuples_string_types()

    >>> a is b

    False

    >>> a is c

    False

    >>> b is c

    False

    """

    return ('a', 'bc'), (u'a', u'bc'), (b'a', b'bc')

@cython.test_assert_path_exists("//ReturnStatNode//TupleNode",

                                "//ReturnStatNode//TupleNode[@is_literal = false]")

@cython.test_fail_if_path_exists("//ReturnStatNode//TupleNode[@is_literal = true]")

def return_nonconstant_tuple():

    """

    >>> return_nonconstant_tuple()

    ('a', 1, 'd')

    """

    a = eval("1")

    return ('a', a, 'd')