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How does “do something OR DIE()” work in PHP?
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PHP's or works like C's || (which incidentally is also supported by PHP - or just looks nicer and has different operator precedence - see this page).
It's known as a short-circuit operator because it will skip any evaluations once it has enough information to d...
Backbone.js fetch with parameters
Following the documentation , I did:
4 Answers
4
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Run task only if host does not belong to a group
...ariable as documented here: https://docs.ansible.com/ansible/latest/user_guide/playbooks_variables.html#accessing-information-about-other-hosts-with-magic-variables :
group_names is a list (array) of all the groups the current host is in.
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Submitting a multidimensional array via POST with php
...T[$varName])) {
foreach ( $_POST[$varName] as $var ) { // multidimensional POST array elements
$retArray[]=$var;
}
}
$retVal=$retArray;
}
elseif (isset($_POST[$varName]) ) { // simple POST array element
$retVal = $_POST[$var...
Create a CSV File for a user in PHP
...blequotes around your fields, and don't forget to replace double-quotes inside fields to double double-quotes: `echo '"'.str_replace('"','""',$record1).'","'.str_replace....
– Mala
Jul 1 '10 at 21:21
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How do I make many-to-many field optional in Django?
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@omouse I think yes, blank is for django validation, and null for the database. In this kind of case (like for IntegerField) it makes no sense to put one without the other I think
– lajarre
Oct 26 '12 at 15:46
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Use curly braces to initialize a Set in Python
...comprehensive syntax to initialize sets:
>>> a = {x for x in """didn't know about {} and sets """ if x not in 'set' }
>>> a
set(['a', ' ', 'b', 'd', "'", 'i', 'k', 'o', 'n', 'u', 'w', '{', '}'])
share
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Java volatile reference vs. AtomicReference
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No, there is not.
The additional power provided by AtomicReference is the compareAndSet() method and friends. If you do not need those methods, a volatile reference provides the same semantics as AtomicReference.set() and .get().
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Difference Between Invoke and DynamicInvoke
...ype, you can use Invoke, which is very fast - everything is already pre-validated. For example:
Func<int,int> twice = x => x * 2;
int i = 3;
int j = twice.Invoke(i);
// or just:
int j = twice(i);
However! If you just know that it is Delegate, it has to resolve the parameters etc manually...
jQuery / Javascript - How do I convert a pixel value (20px) to a number value (20)
...ut I'd like to be able to use X("20em") for example and get back the true width in pixels.
– Lawrence I. Siden
May 20 '11 at 22:53
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