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is_null($x) vs $x === null in PHP [duplicate]
... three if you count isset() ) methods to determine if a value is null: is_null() and === null . I have heard, but not confirmed, that === null is faster, but in a code review someone strongly suggested that I use is_null() instead as it is specifically designed for the null-evaluation purpo...
MongoDB and “joins” [duplicate]
...is to do it manually, as you have almost described. Just save a document's _id in another document's other_id, then write your own function to resolve the relationship. The other solution is to use DBRefs as described on the manual page above, which will make MongoDB resolve the relationship client-...
Why should I prefer to use member initialization lists?
...t constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the constructor for B will call the default constructor for A, and then initialize a.x to 3. A better ...
Can Selenium Webdriver open browser windows silently in background?
...river
from selenium.webdriver.chrome.options import Options
CHROME_PATH = '/usr/bin/google-chrome'
CHROMEDRIVER_PATH = '/usr/bin/chromedriver'
WINDOW_SIZE = "1920,1080"
chrome_options = Options()
chrome_options.add_argument("--headless")
chrome_options.add_argument(...
Do sealed classes really offer performance Benefits?
... Release build configuration) emits identical MSIL, which is as follows:
L_0000: newobj instance void <NormalClass or SealedClass>::.ctor()
L_0005: stloc.0
L_0006: ldloc.0
L_0007: ldstr "a string"
L_000c: callvirt instance void <NormalClass or SealedClass>::WriteIt(string)
L_0011: ret...
How do I count the number of occurrences of a char in a String?
...n Android, where there is no StringUtils class
– Jose_GD
Nov 6 '12 at 13:12
43
...
git: How to ignore all present untracked files?
...m a git status line such as the one for this file here: ?? app/views/static_pages/contact.html.erb, you would remove the first letter of app. So the command is correct, but the explanation is faulty.
– 7stud
Sep 10 '14 at 21:03
...
Static methods - How to call a method from another method?
...
class.method should work.
class SomeClass:
@classmethod
def some_class_method(cls):
pass
@staticmethod
def some_static_method():
pass
SomeClass.some_class_method()
SomeClass.some_static_method()
sha...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...othername".
Stop the machine from provisioning:
Create a file named action_provision in the same dir as the id file, set it's contents to: 1.5:{id} replacing {id} with the id found in step 1.
Setup a new public/private key:
Vagrant uses a private key stored in .vagrant/machines/default/virtualbox/...
HTML-encoding lost when attribute read from input field
...b/kirillosenkov/archive/2010/03/19/… fishbowl.pastiche.org/2003/07/01/the_curse_of_apos
– Anentropic
Jan 3 '12 at 12:34
5
...