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How to implement __iter__(self) for a container object (Python)
... to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
yield 5
yield from some_list
Pre-3.3, yield from didn't exist, so you would have to do:
def __iter__(self):
yield 5
for x in some_list:
yield x
...
What does functools.wraps do?
...g
def f(x):
"""does some math"""
return x + x * x
f = logged(f)
and your function f is replaced with the function with_logging. Unfortunately, this means that if you then say
print(f.__name__)
it will print with_logging because that's the name of your new function. In fact, if you lo...
How to avoid having class data shared among instances?
...ring the variables inside the class declaration makes them "class" members and not instance members. Declaring them inside the __init__ method makes sure that a new instance of the members is created alongside every new instance of the object, which is the behavior you're looking for.
...
What would a “frozen dict” be?
...self._d[key]
def __hash__(self):
# It would have been simpler and maybe more obvious to
# use hash(tuple(sorted(self._d.iteritems()))) from this discussion
# so far, but this solution is O(n). I don't know what kind of
# n we are going to run into, but sometime...
Class method differences in Python: bound, unbound and static
...
In Python, there is a distinction between bound and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to...
How do I get the path and name of the file that is currently executing?
...vide an example? I've answered similar question using inspect.getabsfile() and it worked for all cases that I've tried.
– jfs
Apr 5 '14 at 17:04
4
...
How to set the prototype of a JavaScript object that has already been instantiated?
...e I have an object foo in my JavaScript code. foo is a complex object and it is generated somewhere else. How can I change the prototype of the foo object?
...
How to make a class property? [duplicate]
... in self.__dict__:
obj = self.__dict__.get(key)
if obj and type(obj) is ClassPropertyDescriptor:
return obj.__set__(self, value)
return super(ClassPropertyMetaClass, self).__setattr__(key, value)
# and update class define:
# class Bar(object):
# _...
Is it possible to print a variable's type in standard C++?
... update to a very old question: Print variable type in C++.
The accepted (and good) answer is to use typeid(a).name(), where a is a variable name.
Now in C++11 we have decltype(x), which can turn an expression into a type. And decltype() comes with its own set of very interesting rules. For exam...
Calling class staticmethod within the class body?
When I attempt to use a static method from within the body of the class, and define the static method using the built-in staticmethod function as a decorator, like this:
...