>> 2011/4/29 Roy Hyunjin Han <starsareblueandfara...@gmail.com>:
>> It would be convenient if replacing items in a dictionary returns the
>> new dictionary, in a manner analogous to str.replace(). What do you
>> think?
>>
>> # Current behavior
>> x = {'key1': 1}
>> x.update(key1=3) == None
>> x == {'key1': 3} # Original variable has changed
>>
>> # Possible behavior
>> x = {'key1': 1}
>> x.replace(key1=3) == {'key1': 3}
>> x == {'key1': 1} # Original variable is unchanged
>>
> 2011/5/5 Giuseppe Ottaviano <giu...@gmail.com>:
> In general nothing stops you to use a proxy object that returns itself
> after each method call, something like
>
> class using(object):
> def __init__(self, obj):
> self._wrappee = obj
>
> def unwrap(self):
> return self._wrappee
>
> def __getattr__(self, attr):
> def wrapper(*args, **kwargs):
> getattr(self._wrappee, attr)(*args, **kwargs)
> return self
> return wrapper
>
>
> d = dict()
> print using(d).update(dict(a=1)).update(dict(b=2)).unwrap()
> # prints {'a': 1, 'b': 2}
> l = list()
> print using(l).append(1).append(2).unwrap()
> # prints [1, 2]
Cool! I never thought of that. That's a great snippet.
I'll forward this to the python-ideas list. I don't think the
python-dev people want this discussion to continue on their mailing
list.
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
