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unique object identifier in javascript
... var id = 0;
Object.id = function(o) {
if ( typeof o.__uniqueid == "undefined" ) {
Object.defineProperty(o, "__uniqueid", {
value: ++id,
enumerable: false,
// This could go either way, depending on your...
Does python have an equivalent to Java Class.forName()?
...honic way of doing it.
Here's a function that does what you want:
def get_class( kls ):
parts = kls.split('.')
module = ".".join(parts[:-1])
m = __import__( module )
for comp in parts[1:]:
m = getattr(m, comp)
return m
You can use the return value of this ...
How to reliably open a file in the same directory as a Python script
...
I always use:
__location__ = os.path.realpath(
os.path.join(os.getcwd(), os.path.dirname(__file__)))
The join() call prepends the current working directory, but the documentation says that if some path is absolute, all other paths lef...
Among $_REQUEST, $_GET and $_POST which one is the fastest?
...
$_REQUEST, by default, contains the contents of $_GET, $_POST and $_COOKIE.
But it's only a default, which depends on variables_order ; and not sure you want to work with cookies.
If I had to choose, I would probably not us...
What are “named tuples” in Python?
...e following:
pt1 = (1.0, 5.0)
pt2 = (2.5, 1.5)
from math import sqrt
line_length = sqrt((pt1[0]-pt2[0])**2 + (pt1[1]-pt2[1])**2)
Using a named tuple it becomes more readable:
from collections import namedtuple
Point = namedtuple('Point', 'x y')
pt1 = Point(1.0, 5.0)
pt2 = Point(2.5, 1.5)
from ...
Underscore vs Double underscore with variables and methods [duplicate]
Somebody was nice enough to explain to me that __method() mangles but instead of bothering him further since there are a lot of other people who need help I was wondering if somebody could elaborate the differences further.
...
Python constructors and __init__
...ame but different arguments.
In your code example, you're not overloading __init__(). What happens is that the second definition rebinds the name __init__ to the new method, rendering the first method inaccessible.
As to your general question about constructors, Wikipedia is a good starting point....
Creating a singleton in Python
... a base class. Here is a sample implementation:
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
return cls._instances[cls]
class...
What does the “at” (@) symbol do in Python?
...
Example
class Pizza(object):
def __init__(self):
self.toppings = []
def __call__(self, topping):
# When using '@instance_of_pizza' before a function definition
# the function gets passed onto 'topping'.
self.toppings.appe...
What is a clean, pythonic way to have multiple constructors in Python?
...d a definitive answer for this. As far as I know, you can't have multiple __init__ functions in a Python class. So how do I solve this problem?
...