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define() vs. const
...d in const as well:
const BIT_5 = 1 << 5; // Valid since PHP 5.6 and invalid previously
define('BIT_5', 1 << 5); // Always valid
const takes a plain constant name, whereas define() accepts any expression as name. This allows to do things like this:
for ($i = 0; $i < 32; ++$i) {
...
How do I make a column unique and index it in a Ruby on Rails migration?
...1 for suggesting continuing to use the validates_uniqueness_of. The error handling is much cleaner using this method for the cost of a single indexed query I would suggest he does both
– Steve Weet
Sep 19 '09 at 22:08
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What does new self(); mean in PHP?
...ends MyParentClass {
}
$a = MyChildClass::getInstance();
var_dump($a);
And you'd get this kind of output :
object(MyParentClass)#1 (0) { }
Which means self means MyParentClass -- i.e. here too, the class in which it is written.
With PHP < 5.3, that "the class in which it is written" ...
Circular dependency in Spring
How does Spring resolve this: bean A is dependent on bean B, and bean B on bean A.
12 Answers
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Detect when an image fails to load in Javascript
... tester.src=URL;
}
function imageFound() {
alert('That image is found and loaded');
}
function imageNotFound() {
alert('That image was not found.');
}
testImage("http://foo.com/bar.jpg");
And my sympathies for the jQuery-resistant boss!
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Error when installing windows SDK 7.1
...as of now) is called Microsoft Visual C++ 2010 SP1 Redistributable Package and is version 10.0.40219.1. Too k me a while to figure out I needed to search for SP1, so leaving this here for others.
– Terrabits
May 31 '18 at 17:29
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Change the name of the :id parameter in Routing resources for Rails
I looked around on how to change the dynamic params slot and found this post that does the exact thing.
The post is https://thoughtbot.com/blog/rails-patch-change-the-name-of-the-id-parameter-in
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Excel VBA App stops spontaneously with message “Code execution has been halted”
...expected solution for a bizarre problem. After pressing [Ctrl+Break] twice and continuing, I saved the file. After that, the problem no longer appeared when I closed and re-opened the file.
– dbenham
Oct 1 '12 at 16:59
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Detecting if an NSString contains…?
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Actually you can just add space on the beginning and end of the string and " is " will match string begins with "is"
– user4951
Nov 12 '12 at 7:41
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Command not found when using sudo
...file must have an executable permission bit set.
In order to fully understand Linux file permissions you can study the documentation for the chmod command. chmod, an abbreviation of change mode, is the command that is used to change the permission settings of a file.
To read the chmod documentatio...