On Tue, Dec 15, 2020 at 02:24:48PM +0300, Paul Sokolovsky wrote:
> As I showed right in my first mail, in "a.b()",
> "a.b" doesn't get evaluated at all (since CPython3.7).
`a.b` still has to be looked up, even with the new fast LOAD_METHOD
byte-code. The difference is that it may be able to avoid instantiating
a MethodType object, since that would be immediately garbage-collected
once the function object it wraps is called.
The lookup still has to take place:
```
>>> class Demo:
... def __getattribute__(self, name):
... if name == 'method':
... print("looked up method")
... return super().__getattribute__(name)
... def method(self):
... print("called method")
...
>>> obj = Demo()
>>> obj.method()
looked up method
called method
```
If the above example doesn't convince you that you are mistaken, how
about this?
```
>>> class Demo2:
... def __getattr__(self, name):
... print("evaluating obj.%s" % name)
... return lambda: print("calling method")
...
>>> obj = Demo2()
>>> obj.method()
evaluating obj.method
calling method
```
In this second demonstration, obj.method *doesn't even exist* ahead of
time and has to be created dynamically on attribute lookup, before it
can be called.
--
Steve
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