cython

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# mode: run
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# tag: generators, lambda
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def genexpr():
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    """
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    >>> genexpr()
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    [0, 2, 4, 6, 8]
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    """
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    x = 'abc'
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    result = list( x*2 for x in range(5) )
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    assert x == 'abc' # don't leak
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    return result
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def genexpr_if():
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    """
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    >>> genexpr_if()
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    [0, 4, 8]
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    """
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    x = 'abc'
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    result = list( x*2 for x in range(5) if x % 2 == 0 )
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    assert x == 'abc' # don't leak
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    return result
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def genexpr_if_false():
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    """
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    >>> genexpr_if_false()
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    []
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    """
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    x = 'abc'
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    result = list( x*2 for x in range(5) if False )
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    assert x == 'abc' # don't leak
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    return result
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def genexpr_with_lambda():
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    """
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    >>> genexpr_with_lambda()
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    [0, 4, 8]
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    """
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    x = 'abc'
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    result = list( x*2 for x in range(5) if (lambda x:x % 2)(x) == 0 )
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    assert x == 'abc' # don't leak
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    return result
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def genexpr_of_lambdas(int N):
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    """
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    >>> [ (f(), g()) for f,g in genexpr_of_lambdas(5) ]
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    [(0, 0), (1, 2), (2, 4), (3, 6), (4, 8)]
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    """
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    return ( ((lambda : x), (lambda : x*2)) for x in range(N) )
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def genexpr_with_bool_binop(values):
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    """
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    >>> values = [(1, 2, 3), (None, 4, None), (5, None, 6)]
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    >>> genexpr_with_bool_binop(values)
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    [(1, 2, 3), ('X', 4, 'X'), (5, 'X', 6)]
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    """
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    # copied from CPython's test_itertools.py
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    return [tuple((e is None and 'X' or e) for e in t) for t in values]
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