Hi Pythonistas,
I'm stuck in a maze of new style classes and generators. While I love the
concepts, I obviously didn't grok them throughout.
I'm trying to generate a bunch of similar classes, where some are contained
in list attributes of others, e.g.:
class A:
def __init__(self):
self.id = 'A1'
self.b = [instances of B]
class B:
def __init__(self):
self.id = 'B1'
Here's the test code, I have:
#!/usr/bin/env python
# -*- coding: utf8 -*-
class A(object):
"A"
def __init__(self):
self.id = None
self.b = []
class B(object):
"B"
def __init__(self):
self.id = None
class Gen(object):
def records(self, cls):
for i in range(3):
setattr(cls, "id", "%s%s" % (cls.__doc__, i))
yield cls
def display(self, rec):
for i in rec.__dict__.keys():
if not i.startswith("_"):
print "%s: %s: %s" % (rec.__doc__, i, rec.__dict__[i])
class GenA(Gen):
def __init__(self):
self.genB = GenB()
def records(self):
for a in Gen.records(self, A()):
for b in self.genB.records():
#self.genB.display(b)
a.b.append(b)
#self.display(a)
yield a
class GenB(Gen):
def records(self):
return Gen.records(self, B())
# testing..
aRecs = []
bRecs = []
for i, r in enumerate(GenB().records()):
bRecs.append(r)
print i, r.id, r
for i, r in enumerate(GenA().records()):
aRecs.append(r)
print i, r.id, r
for b in r.b:
print b.id, b
Here's the commented output:
# even if I keep a reference to each rec, the object is reused:
0 B0 <__main__.B object at 0xb7bd0f8c>
1 B1 <__main__.B object at 0xb7bd0f8c>
2 B2 <__main__.B object at 0xb7bd0f8c>
# same here, with additional quadratic behavior, I do not understand
0 A0 <__main__.A object at 0xb7bd206c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
1 A1 <__main__.A object at 0xb7bd206c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd20ec>
B2 <__main__.B object at 0xb7bd20ec>
B2 <__main__.B object at 0xb7bd20ec>
2 A2 <__main__.A object at 0xb7bd206c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd210c>
B2 <__main__.B object at 0xb7bd20ec>
B2 <__main__.B object at 0xb7bd20ec>
B2 <__main__.B object at 0xb7bd20ec>
B2 <__main__.B object at 0xb7bd0f8c>
B2 <__main__.B object at 0xb7bd0f8c>
B2 <__main__.B object at 0xb7bd0f8c>
I expected to get 3 different class objects from both sections, with each A
containing 3 different Bs in the latter section, but obviously got
something else.
Could some kind soul help me to distangle my mind twist here? Am I healable?
TIA, Pete
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