9

I'm wondering if there's a way to list all the special methods (like __getattr__, __lt__) programmatically instead of going to the Python data model documentation and copy paste all of them. Since I can use dir(builtins) to retrieve a list of builtin identifiers, so I was hoping there's also a way for the special methods.

jonrsharpe
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Bubble Bubble Bubble Gut
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  • `dir(builtins)` will also give you `quit` and `exit` that are added by `site.py` but are not actually part of the builr-in functions documentation. -- Edit: Nvm they are actually documented here: https://docs.python.org/3/library/constants.html#built-in-consts – Niklas R Jul 27 '18 at 17:03
  • Related: https://stackoverflow.com/a/38345345/3001761 – jonrsharpe Jul 27 '18 at 17:04
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    I doubt it. There's nothing really "special" about the special methods. You could easily require write a function that required its inputs to have a `__foo__` method, and that would be just as meaningful as `__len__` or `__getattr__` – Patrick Haugh Jul 27 '18 at 17:04
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    Are you doing something with the list in a program? Or just need it as a convenient reference? – Ry- Jul 27 '18 at 17:08
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    See this, https://stackoverflow.com/questions/8920341/finding-a-list-of-all-double-underscore-variables – Marcus.Aurelianus Jul 27 '18 at 17:09

1 Answers1

11

No, there isn't a canonical way to get that from the language itself. You're stuck with the documentation (which is not a bad thing).

I mean, you could always do that

>>> import re, requests
>>> set(re.findall('__\w+__', requests.get('https://docs.python.org/3/reference/datamodel.html').text))
set(['__abs__',
     '__add__',
     '__aenter__',
     '__aexit__',
     '__aiter__',
     '__and__',
     '__anext__',
     '__annotations__',
     '__await__',
     '__bases__',
     '__bool__',
     '__bytes__',
     '__call__',
     '__ceil__',
     '__class__',
     '__class_getitem__',
     '__classcell__',
     '__closure__',
     '__code__',
     '__complex__',
     '__contains__',
     '__defaults__',
     '__del__',
     '__delattr__',
     '__delete__',
     '__delitem__',
     '__dict__',
     '__dir__',
     '__divmod__',
     '__doc__',
     '__enter__',
     '__eq__',
     '__exit__',
     '__file__',
     '__float__',
     '__floor__',
     '__floordiv__',
     '__format__',
     '__func__',
     '__future__',
     '__ge__',
     '__get__',
     '__getattr__',
     '__getattribute__',
     '__getitem__',
     '__globals__',
     '__gt__',
     '__hash__',
     '__iadd__',
     '__iand__',
     '__ifloordiv__',
     '__ilshift__',
     '__imatmul__',
     '__imod__',
     '__import__',
     '__imul__',
     '__index__',
     '__init__',
     '__init_subclass__',
     '__instancecheck__',
     '__int__',
     '__invert__',
     '__ior__',
     '__ipow__',
     '__irshift__',
     '__isub__',
     '__iter__',
     '__itruediv__',
     '__ixor__',
     '__kwdefaults__',
     '__le__',
     '__len__',
     '__length_hint__',
     '__lshift__',
     '__lt__',
     '__matmul__',
     '__missing__',
     '__mod__',
     '__module__',
     '__mro__',
     '__mro_entries__',
     '__mul__',
     '__name__',
     '__ne__',
     '__neg__',
     '__new__',
     '__next__',
     '__objclass__',
     '__or__',
     '__pos__',
     '__pow__',
     '__prepare__',
     '__qualname__',
     '__radd__',
     '__rand__',
     '__rdivmod__',
     '__repr__',
     '__reversed__',
     '__rfloordiv__',
     '__rlshift__',
     '__rmatmul__',
     '__rmod__',
     '__rmul__',
     '__ror__',
     '__round__',
     '__rpow__',
     '__rrshift__',
     '__rshift__',
     '__rsub__',
     '__rtruediv__',
     '__rxor__',
     '__self__',
     '__set__',
     '__set_name__',
     '__setattr__',
     '__setitem__',
     '__slots__',
     '__str__',
     '__sub__',
     '__subclasscheck__',
     '__traceback__',
     '__truediv__',
     '__trunc__',
     '__weakref__',
     '__xor__'])
nosklo
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