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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
What is the definition of “interface” in object oriented programming
... one of the more overloaded and confusing terms in development.
It is actually a concept of abstraction and encapsulation. For a given "box", it declares the "inputs" and "outputs" of that box. In the world of software, that usually means the operations that can be invoked on the box (along with ar...
Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...
How to use Elasticsearch with MongoDB?
... instance.
Make sure everything is up to date.
sudo apt-get update
Install NodeJS.
sudo apt-get install nodejs
sudo apt-get install npm
Install MongoDB - These steps are straight from MongoDB docs.
Choose whatever version you're comfortable with. I'm sticking with v2.4.9 because it seems to b...
Google Maps API v3: How to remove all markers?
In Google Maps API v2, if I wanted to remove all the map markers, I could simply do:
31 Answers
...
Unix - create path of folders and file
...her/path/here && touch $_/cpredthing.txt. The $_ expands to essentially the "last argument in the last command executed".
– Sgnl
Apr 19 '16 at 1:37
4
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Macro vs Function in C
...uct webpage page;
page.numButtons = 2;
num_button_holes(page) -> 8
Finally, macros can be difficult to debug, producing weird syntax errors or runtime errors that you have to expand to understand (e.g. with gcc -E), because debuggers cannot step through macros, as in this example:
#define prin...
When should I use the Visitor Design Pattern? [closed]
...want to make the fewest possible modifications to it.
The Visitor pattern allows you to move each new operation in a suitable class, and you need to extend the hierarchy's interface only once. Let's do it. First, we define an abstract operation (the "Visitor" class in GoF) which has a method for ev...
What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
...es <limits.h> are applicable.
In terms of long double, that's actually a floating point value rather than an integer. Similarly to the integral types, it's required to have at least as much precision as a double and to provide a superset of values over that type (meaning at least those valu...
How assignment works with Python list slice?
...
To be clear, "takes a slice of" really means "make a copy of a slice of" which is where part of the confusion comes from.
– Mark Ransom
May 16 '12 at 17:12
...