After looking into the \tkiniter\font.py source file, triggered by Jim's
hint on my previous subject "Why an object changes its "address" between
adjacent calls?", I get more confused.
Below was quoted from the font.py:
------------------------
def nametofont(name):
"""Given the name of a tk named font, returns a Font representation.
"""
return Font(name=name, exists=True)
class Font:
"""Represents a named font.
Constructor options are:
...
exists -- does a named font by this name already exist?
Creates a new named font if False, points to the existing font
if True.
...
"""
def __init__(self, root=None, font=None, name=None, exists=False,
**options):
...
----------------------
From my understanding, the __init__ method was called after the instance
was created, that's why the __init__ has a self parameter, right? Then,
how is it possible "...points to the existing font if True"? I didn't
see any clue in __init__ doing this.
I also make a test of my own and it fails too.
>>> class A:
... objs = []
... def __init__(self, exists=False):
... if exists: self = self.objs[0]
... else: self.objs.append(self)
...
>>> a0 = A()
>>> id(a0)
35569968
>>> a1 = A(exists=True)
>>> id(a1)
35572336
What I expect is that id(a0) and id(a1) has the same value. They should
points to the same object.
Best Regards,
Jach Fong
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