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Python memoising/deferred lookup property decorator
...tructor but only upon first read. These attributes do not change over the lifetime of the instance, but they're a real bottleneck to calculate that first time and only really accessed for special cases. Hence they can also be cached after they've been retrieved from the database (this therefore fits...
What is the function __construct used for?
...structor).
You are not required to define a constructor in your class, but if you wish to pass any parameters on object construction then you need one.
An example could go like this:
class Database {
protected $userName;
protected $password;
protected $dbName;
public function __construct ...
Redirecting from HTTP to HTTPS with PHP
...
Try something like this (should work for Apache and IIS):
if (empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] === "off") {
$location = 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
header('HTTP/1.1 301 Moved Permanently');
header('Location: ' . $location);
...
How can I store my users' passwords safely?
... salted hashes: add pepper
If you want extra security, the security folks now (2017) recommend adding a 'pepper' to the (automatically) salted password hashes.
There is a simple, drop in class that securely implements this pattern, I recommend:
Netsilik/PepperedPasswords
(github).
It comes with...
Shared-memory objects in multiprocessing
...s giant array as input (together with some other parameters). func with different parameters can be run in parallel. For example:
...
How to copy an object in Objective-C
...lways with reference types, there are two notions of "copy". I'm sure you know them, but for completeness.
A bitwise copy. In this, we just copy the memory bit for bit - this is what NSCopyObject does. Nearly always, it's not what you want. Objects have internal state, other objects, etc, and ofte...
Count characters in textarea
...why your code doesn't work if what you posted was incomplete, but without knowing that I can't know for sure.
<!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery-1.5.js"></script>
<script>
function countChar(val) {
var...
Does Python have an ordered set?
...Documentation. This runs on Py2.6 or later and 3.0 or later without any modifications. The interface is almost exactly the same as a normal set, except that initialisation should be done with a list.
OrderedSet([1, 2, 3])
This is a MutableSet, so the signature for .union doesn't match that of set...
Two way/reverse map [duplicate]
...rd thing in python where I need to keep track of who's talking to whom, so if Alice --> Bob, then that implies that Bob --> Alice.
...
Get value of a string after last slash in JavaScript
...
When I know the string is going to be reasonably short then I use the following one liner... (remember to escape backslashes)
// if str is C:\windows\file system\path\picture name.jpg
alert( str.split('\\').pop() );
alert pops up ...