Hi all,
I found a surprising behavior regarding new-style classes operator lookup.
It seems that for operators, the instance methods are ignored. Observe: class C:
.... def foo(self):
.... print 'foo'
.... def __setitem__(self, k, v):
.... print 'C.__setitem__', k, v
.... c = C()
c.foo()
foo c[1] = 1
C.__setitem__ 1 1 def my_foo():
.... print 'my_foo'
.... def my_setitem(k, v):
.... print 'my_setitem', k, v
.... c.foo = my_foo
c.__setitem__ = my_setitem
c.foo()
my_foo c[1] = 1
my_setitem 1 1
All is well. Now, if you use a new-style class, the instance method is not
called:
class C(object):
.... def foo(self):
.... print 'foo'
.... def __setitem__(self, k, v):
.... print 'C.__setitem__', k, v
.... c = C()
c.foo()
foo c[1] = 1
C.__setitem__ 1 1 def my_foo():
.... print 'my_foo'
.... def my_setitem(k, v):
.... print 'my_setitem', k, v
.... c.foo = my_foo
c.__setitem__ = my_setitem
c.foo()
my_foo c[1] = 1
C.__setitem__ 1 1 # should print "my_setitem 1 1"
Is this a bug, or am I missing something? Any help would be appreciated.
Regards,
Nicodemus. 0  1146  This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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