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How to override the copy/deepcopy operations for a Python object?
...ully, but this is the first time I've actually gone about overloading the __copy__ and __deepcopy__ methods. I've already Googled around and looked through the built-in Python modules to look for instances of the __copy__ and __deepcopy__ functions (e.g. sets.py , decimal.py , and fracti...
Difference between DirectCast() and CType() in VB.NET
... convert a string to an integer. It has as much power as calling Convert.To___() in C#, where the ___ is the target type of your cast.
This is desirable because it's very powerful. However, this power comes at the cost of performance; it's not as fast as DirectCast() or C#'s cast operator because i...
Are there any standard exit status codes in Linux?
...istd.h>
#include <signal.h>
int main() {
int status;
pid_t child = fork();
if (child <= 0)
exit(42);
waitpid(child, &status, 0);
if (WIFEXITED(status))
printf("first child exited with %u\n", WEXITSTATUS(status));
/* prints: "first child exite...
Web-scraping JavaScript page with Python
...:
import requests
from bs4 import BeautifulSoup
response = requests.get(my_url)
soup = BeautifulSoup(response.text)
soup.find(id="intro-text")
# Result:
<p id="intro-text">No javascript support</p>
Scraping with JS support:
from selenium import webdriver
driver = webdriver.PhantomJS(...
Paging UICollectionView by cells, not screen
...nformance and set a value for pageWidth:
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
let pageWidth = // The width your page should have (plus a possible margin)
let proportionalOffset = collectionView.contentOffset.x / pageWidth
indexOfCellBeforeDragging = Int(round(p...
What's the scope of a variable initialized in an if statement?
...ked only at runtime -- that is, when you get to the print x statement. If __name__ didn't equal "__main__" then you would get an exception: NameError: name 'x' is not defined.
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ios app maximum memory budget
...
iPhone 5 crashes at ±645 MB.
– asp_net
Dec 15 '13 at 21:03
4
@JasperPol I've e...
What is the difference between public, protected, package-private and private in Java?
...
The official tutorial may be of some use to you.
______________________________________________________________
| │ Class │ Package │ Subclass │ Subclass │ World |
| │ │ │(same pkg)│(diff pkg)│ |
|─────...
Select distinct values from a table field
...odel is 'Shop'
class Shop(models.Model):
street = models.CharField(max_length=150)
city = models.CharField(max_length=150)
# some of your models may have explicit ordering
class Meta:
ordering = ('city')
Since you may have the Meta class ordering attribute set, you can us...
Java's L number (long) specification
...tion about suffixes... If I declare a long or a double variable like: long _lo = 30; and not 30L does this mean my variable will be converted into float ? Or in case of _lo = _lo + 2.77 that _lo will be casted into float although it was declared as long
– luigi7up
...