On Fri, Feb 10, 2017 at 8:05 PM, eryk sun <eryk...@gmail.com> wrote:
> Speaking of classes and metaclasses, note that you can't call
> int.__repr__(int) to get this representation, because the __repr__
> special method of int is meant for instances of int such as int(5).
This bit got me experimenting. Since the integer "5" is an integer
object instance, I am wondering why I can't do:
py3: 5.__repr__()
File "<stdin>", line 1
5.__repr__()
^
SyntaxError: invalid syntax
, but I can do:
py3: x = 5
py3: x.__repr__()
'5'
?
More experimentation. Is this how I would define __repr__() for a custom class?
py3: class boB:
... def __repr__(self):
... return "<boB's namesake class>"
...
py3: x = boB()
py3: repr(x)
"<boB's namesake class>"
Seems to work. But in class examples I've seen posted, I do not
recall __repr__ ever being defined. So I infer that most of the time
I should not or need not do so, but under what circumstances should I
do so?
Another curiosity question. If I type:
py3: repr(int)
"<class 'int'>"
I get what I expect, but if I do the same with my custom class, "boB",
I instead get:
py3: repr(boB)
"<class '__main__.boB'>"
Why the difference between the Python class "int" and my custom class
"boB"? Did I not define __repr__() correctly?
--
boB
_______________________________________________
Tutor maillist - Tutor@python.org
To unsubscribe or change subscription options:
https://mail.python.org/mailman/listinfo/tutor
