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https://github.com/micropython/micropython.git
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d1bf0eeb0f
This adds a CPython diff that explains why calling `super().__init__()` is required in MicroPython when subclassing a native type (because `__new__` and `__init__` are not separate functions). Signed-off-by: David Lechner <david@pybricks.com>
32 lines
729 B
Python
32 lines
729 B
Python
"""
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categories: Core,Classes
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description: When inheriting native types, calling a method in ``__init__(self, ...)`` before ``super().__init__()`` raises an ``AttributeError`` (or segfaults if ``MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG`` is not enabled).
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cause: MicroPython does not have separate ``__new__`` and ``__init__`` methods in native types.
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workaround: Call ``super().__init__()`` first.
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"""
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class L1(list):
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def __init__(self, a):
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self.append(a)
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try:
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L1(1)
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print("OK")
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except AttributeError:
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print("AttributeError")
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class L2(list):
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def __init__(self, a):
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super().__init__()
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self.append(a)
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try:
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L2(1)
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print("OK")
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except AttributeError:
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print("AttributeError")
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