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What does new self(); mean in PHP?

... the parent class The first situation would look like this (I've removed all non-necessary code, for this example -- you'll have to add it back to get the singleton behavior)* : class MyParentClass { } class MyChildClass extends MyParentClass { public static function getInstance() { ...
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Types in MySQL: BigInt(20) vs Int(20)

...gInt , MediumInt , and Int are... it would seem obvious that they would allow for larger numbers; however, I can make an Int(20) or a BigInt(20) and that would make seem that it is not necessarily about size. ...
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What are best practices for validating email addresses on iOS 2.0

... ; "]", or "\" Yes, that means +, ', etc are all legit. share | improve this answer | follow | ...
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Best way to assert for numpy.array equality?

..._equal is more reliable. update A few versions ago numpy obtained assert_allclose which is now my favorite since it allows us to specify both absolute and relative error and doesn't require decimal rounding as the closeness criterion. ...
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How to identify server IP address in PHP

... This is NOT the server address! This is the address the remote browser calls the server, which is under control of the remote user. Use the answer by John K instead – Ariel Feb 12 '15 at 10:36 ...
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How can I tell when HttpClient has timed out?

... I found that the best way to determine if the service call has timed out is to use a cancellation token and not the HttpClient's timeout property: var cts = new CancellationTokenSource(); cts.CancelAfter(timeout); And then handle the CancellationException during the s...
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Should I compile with /MD or /MT?

... By dynamically linking with /MD, you are exposed to system updates (for good or ill), your executable can be smaller (since it doesn't have the library embedded in it), and I believe that at very least the code segment of a DLL is...
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Excel: last character/string match in a string

...(2,1/(MID(A4,SEQUENCE(LEN(A4)),2)="YY")) | 4 | Whilst this both allows us to no longer use an arbitrary replacement character and it allows overlapping patterns, the "downside" is the useage of an array. Note: You can force the same behaviour in older Excel versions through either =M...
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Why does volatile exist?

...ed 16 bit value as a semaphore to know when the other guy was done. Essentially we did this: void waitForSemaphore() { volatile uint16_t* semPtr = WELL_KNOWN_SEM_ADDR;/*well known address to my semaphore*/ while ((*semPtr) != IS_OK_FOR_ME_TO_PROCEED); } Without volatile, the optimizer sees ...
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JavaScript listener, “keypress” doesn't detect backspace?

...s invoked only for character (printable) keys, KeyDown event is raised for all including nonprintable such as Control, Shift, Alt, BackSpace, etc. UPDATE: The keypress event is fired when a key is pressed down and that key normally produces a character value Reference. ...