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Update R using RStudio
...
You install a new version of R from the official website.
RStudio should automatically start with the new version when you relaunch it.
In case you need to do it manually, in RStudio, go to :Tools -> options -> General.
Chec...
How to install Hibernate Tools in Eclipse?
What is the proper way to install Hibernate Tools in Eclipse as a plugin?
The Hibernate site doesn't really give any instructions.
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Can one AngularJS controller call another?
...omeDataService)
{
// use the data service, bind to template...
// or call methods on someDataService to send a request to server
}
function SecondController(someDataService)
{
// has a reference to the same instance of the service
// so if the service updates state for example, this contr...
Why are regular expressions so controversial? [closed]
...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs.
– Pacerier
Dec 1 '15 at 21:53
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Elements order in a “for (… in …)” loop
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Quoting John Resig:
Currently all major browsers loop over the properties of an object in the order in
which they were defined. Chrome does this as well, except for a couple cases. [...]
This behavior is explicitly left undefined by the ECMAScript specifi...
Difference between local and global indexes in DynamoDB
...ndary index is
considered "global" because queries on the index can span all of the
data in a table, across all partitions.
Local secondary index — an index that has the same hash key as the
table, but a different range key. A local secondary index is "local"
in the sense that every p...
Removing Java 8 JDK from Mac
So I installed the beta of JDK 8 a while ago to look at some of the examples. I thought for sure by now, it's easy to change between versions.
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Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
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dispatch_once() is absolutely synchronous. Not all GCD methods do things asynchronously (case in point, dispatch_sync() is synchronous). The use of dispatch_once() replaces the following idiom:
+ (MyClass *)sharedInstance {
static MyClass *sharedInstance;
@synchr...
'AND' vs '&&' as operator
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If you use AND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the ...
Can local storage ever be considered secure? [closed]
... with cryptography in client-side (browser) javascript are detailed below. All but one of these concerns does not apply to the WebCrypto API, which is now reasonably well supported.
For an offline app, you must still design and implement a secure keystore.
Aside: If you are using Node.js, use the ...