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Using a dispatch_once singleton model in Swift
...tl;dr: Use the class constant approach if you are using Swift 1.2 or above and the nested struct approach if you need to support earlier versions.
From my experience with Swift there are three approaches to implement the Singleton pattern that support lazy initialization and thread safety.
Class c...
How to delete the contents of a folder?
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If you're working with a very large directory, and particularly a network directory on windows, and you can control the environment in which this program runs, it might be worth using Py3.5's "os.scandir(folder)" function instead of listdir. The syntax is quite different ...
Is it bad practice to make a setter return “this”?
...you know which fields you need to set at the time you're writing the code, and
there are many different combinations for which fields you want to set.
Alternatives to this method might be:
One mega constructor (downside: you might pass lots of nulls or default values, and it gets hard to know w...
What are important languages to learn to understand different approaches and concepts? [closed]
When all you have is a pair of bolt cutters and a bottle of vodka, everything looks like the lock on the door of Wolf Blitzer's boathouse. (Replace that with a hammer and a nail if you don't read xkcd)
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How to dump a table to console?
...mp it to std out or the console via a print statement or something quick and dirty but I can't figure out how. I'm looking for the rough equivalent that I'd get when printing an NSDictionary using gdb.
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$on and $broadcast in angular
I have a footerController and codeScannerController with different views.
4 Answers
4
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Deleting an element from an array in PHP
...n use unset() or alternatively \array_splice().
Also if you have the value and don't know the key to delete the element you can use \array_search() to get the key.
unset()
Note that when you use unset() the array keys won't change/reindex. If you want to reindex the keys you can use \array_values() ...
When does invoking a member function on a null instance result in undefined behavior?
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Both (a) and (b) result in undefined behavior. It's always undefined behavior to call a member function through a null pointer. If the function is static, it's technically undefined as well, but there's some dispute.
The first thin...
RESTful API methods; HEAD & OPTIONS
I'm writing a RESTful API module for an application in PHP, and I'm a bit mixed on the verbs HEAD and OPTIONS .
3 Answer...
Converting between datetime, Timestamp and datetime64
...d by np.datetime64 as time in UTC.
To convert datetime to np.datetime64 and back (numpy-1.6):
>>> np.datetime64(datetime.utcnow()).astype(datetime)
datetime.datetime(2012, 12, 4, 13, 34, 52, 827542)
It works both on a single np.datetime64 object and a numpy array of np.datetime64.
Th...