2011/5/24 Georg Brandl :

On 24.05.2011 18:08, benjamin.peterson wrote:

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http://hg.python.org/cpython/rev/8f403199f999 changeset:   70331:8f403199f999 user:        Benjamin Peterson date:        Tue May 24 11:09:06 2011 -0500 summary:   move specialized dir implementations into __dir__ methods (closes #12166)

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+static PyMethodDef module_methods[] = { +    {"__dir__", module_dir, METH_NOARGS, +     PyDoc_STR("__dir__() -> specialized dir() implementation")}, +    {0} +};

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 static PyMethodDef type_methods[] = {      {"mro", (PyCFunction)mro_external, METH_NOARGS,       PyDoc_STR("mro() -> list\nreturn a type's method resolution order")}, @@ -2585,6 +2661,8 @@       PyDoc_STR("__instancecheck__() -> check if an object is an instance")},      {"__subclasscheck__", type___subclasscheck__, METH_O,       PyDoc_STR("__subclasscheck__() -> check if a class is a subclass")}, +    {"__dir__", type_dir, METH_NOARGS, +     PyDoc_STR("__dir__() -> specialized __dir__ implementation for types")},

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 static PyMethodDef object_methods[] = {      {"__reduce_ex__", object_reduce_ex, METH_VARARGS,       PyDoc_STR("helper for pickle")}, @@ -3449,6 +3574,8 @@       PyDoc_STR("default object formatter")},      {"__sizeof__", object_sizeof, METH_NOARGS,       PyDoc_STR("__sizeof__() -> size of object in memory, in bytes")}, +    {"__dir__", object_dir, METH_NOARGS, +     PyDoc_STR("__dir__() -> default dir() implementation")},

This is interesting: I though we use "->" to specify the return value (or its type).  __instancecheck__ and __subclasscheck__ set a different precedent, while __sizeof__ follows.

Yes, I was wondering about that, so I just picked one. :) "->" seems to be better for return values, though, given the resemblance to annotations. -- Regards, Benjamin