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Double Negation in C++
...ompiler warning. Try this:
int _tmain(int argc, _TCHAR* argv[])
{
int foo = 5;
bool bar = foo;
bool baz = !!foo;
return 0;
}
The 'bar' line generates a "forcing value to bool 'true' or 'false' (performance warning)" on MSVC++, but the 'baz' line sneaks through fine.
...
How to keep environment variables when using sudo
...
To allow -E (preserve environment) for wget, you need to specify the SETENV tag on the sudo rule that allows the running of wget -- Example: <username> ALL=(root) NOPASSWD:SETENV: <path to wget>
...
Why is using 'eval' a bad practice?
...d eval have nothing to do with each other. An application that's fundamentally mis-designed is fundamentally mis-designed. eval is no more the root cause of bad design than division by zero or attempting to import a module which is known not to exist. eval isn't insecure. Applications are insecu...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
Number of elements in a javascript object
...
Although JS implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly ite...
How can I use UUIDs in SQLAlchemy?
... dialect supports UUID columns. This is easy (and the question is specifically postgres) -- I don't understand why the other answers are all so complicated.
Here is an example:
from sqlalchemy.dialects.postgresql import UUID
from flask_sqlalchemy import SQLAlchemy
import uuid
db = SQLAlchemy()
...
Check whether variable is number or string in JavaScript
...ject.prototype.toString;
_.isString = function (obj) {
return toString.call(obj) == '[object String]';
}
This returns a boolean true for the following:
_.isString("Jonathan"); // true
_.isString(new String("Jonathan")); // true
...
Log exception with traceback
... log file
ERROR:root:Got exception on main handler
Traceback (most recent call last):
File "/tmp/teste.py", line 9, in <module>
run_my_stuff()
NameError: name 'run_my_stuff' is not defined
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How do I detect a click outside an element?
...instead of the jQuery part.
But element.closest() is now also available in all major browsers (the W3C version differs a bit from the jQuery one).
Polyfills can be found here: Element.closest()
Edit – 2020-05-21
In the case where you want the user to be able to click-and-drag inside the element, t...
phpunit mock method multiple calls with different arguments
...s for different input arguments? For example, I have database layer class called DB. This class has method called "Query ( string $query )", that method takes an SQL query string on input. Can I create mock for this class (DB) and set different return values for different Query method calls that dep...