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What does = +_ mean in JavaScript
...ample:
+"1"
cast "1" to pure number 1.
var _ = "1";
var r = +_;
r is now 1, not "1".
Moreover, according to the MDN page on Arithmetic Operators:
The unary plus operator precedes its operand and evaluates to its
operand but attempts to converts it into a number, if it isn't
already. [...
How to set Python's default version to 3.x on OS X?
...
This way, your alias will work across shells.
With this, python command now invokes python3. If you want to invoke the "original" python (that refers to python2) on occasion, you can use command python, which will leaving the alias untouched, and works in all shells.
If you launch interpreters m...
Get local IP address
... is right - if there are more than 1 IP address given to you, you need to know which network you're using. Guessing by taking the first or last is not the correct solution.
– gbjbaanb
Sep 4 '13 at 9:11
...
C++ mark as deprecated
...llows for the attribute to be in the same places as __declspec(deprecated) now, so the macro can be simplified.
– bames53
Nov 29 '12 at 17:06
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'is' versus try cast with null check
... casts seem to be performed as fast as they used to be but as and linq are now approximately 3 times faster.
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How much is the overhead of smart pointers compared to normal pointers in C++?
...e, and soon shared_ptrs become the default memory management technique. So now you have repeated 1-3% abstraction penalties which are taken over and over again.
– Nathan Doromal
Nov 27 '19 at 14:53
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How to set a value of a variable inside a template code?
...rary()
@register.assignment_tag
def get_addressee():
return "World"
Now you may use the get_addressee template tag in your templates:
{% load hello_world %}
{% get_addressee as addressee %}
<html>
<body>
<h1>hello {{addressee}}</h1>
</body>
<...
unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
...
What is memoization and how can I use it in Python?
... return k * factorial(k - 1)
factorial = Memoize(factorial)
A feature known as "decorators" was added in Python 2.4 which allow you to now simply write the following to accomplish the same thing:
@Memoize
def factorial(k):
if k < 2: return 1
return k * factorial(k - 1)
The Python D...
Python division
...2.7 and Python 3.3.
In Python 2.7 and Python 3.3:
>>>20//15
1
Now, see the comparison
>>>a = 7.0/4.0
>>>b = 7/4
>>>print a == b
For the above program, the output will be False in Python 2.7 and True in Python 3.3.
In Python 2.7 a = 1.75 and b = 1.
In Pyth...