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How can jQuery deferred be used?
...ore it's returned immediately from the cache. Otherwise, an AJAX request fetches the data and adds it to the cache. The $.when/.then doesn't care about any of this; all you need to be concerned about is using the response, which is passed to the .then() handler in both cases. jQuery.when() handles...
What is the use of hashCode in Java?
...ed for bucketing in Hash implementations like HashMap, HashTable, HashSet, etc.
The value received from hashCode() is used as the bucket number for storing elements of the set/map. This bucket number is the address of the element inside the set/map.
When you do contains() it will take the hash cod...
JavaScript: How to find out if the user browser is Chrome?
...t this, here's the code I used which excluded Edge, Maxthon, iOS safari ...etc var is_chrome = ((navigator.userAgent.toLowerCase().indexOf('chrome') > -1) &&(navigator.vendor.toLowerCase().indexOf("google") > -1));
– Alex C.
Mar 1 '16 at 16:09
...
Get class name of object as string in Swift
...ct can be an instance variable like array, a dictionary, an Int, a NSDate, etc.
Because NSObject is the root class of most Objective-C class hierarchies, you could try to make an extension for NSObject to get the class name of every subclass of NSObject. Like this:
extension NSObject {
var the...
How does PHP 'foreach' actually work?
...ointer backup+restore mechanism is that changes to the IAP through reset() etc. usually do not impact foreach. For example, the following code executes as if the reset() were not present at all:
$array = [1, 2, 3, 4, 5];
foreach ($array as &$value) {
var_dump($value);
reset($array);
}
/...
Email validation using jQuery
...ins becoming more common this regex may need modifying .systems and .poker etc are all valid TLDs now but would fail the regex check
– Liath
Sep 5 '14 at 7:35
3
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Unit testing with Spring Security
...ent: session-scoped in a Servlet container, thread-scoped in a JUnit test, etc. The real limiting factor of a Singleton is when it provides an implementation that is inflexible to different environments.
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Programmatically find the number of cores on a machine
...umCPU = sysconf(_SC_NPROCESSORS_ONLN);
FreeBSD, MacOS X, NetBSD, OpenBSD, etc.
int mib[4];
int numCPU;
std::size_t len = sizeof(numCPU);
/* set the mib for hw.ncpu */
mib[0] = CTL_HW;
mib[1] = HW_AVAILCPU; // alternatively, try HW_NCPU;
/* get the number of CPUs from the system */
sysctl(mib, ...
How to Correctly Use Lists in R?
...where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different lists. x has four vectors, each of length 1. x2 has 1 vector of length 4:
> length(x[[1]])
[1] 1
> length(x2[[1]])
[1] 4
So these are completely different lists.
R l...
When should I use the new keyword in C++?
...nded to any resource that must be acquired and released. (network sockets, files, database connections, synchronization locks). All of them can be acquired in the constructor, and released in the destructor, so you're guaranteed that all resources you acquire will get freed again.
As a general rule...