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Swift variable decorations with “?” (question mark) and “!” (exclamation mark)

I understand that in Swift all variables must be set with a value, and that by using optionals we can set a variable to be set to nil initially. ...
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MYSQL OR vs IN performance

... not believe people who give their "opinion", science is all about testing and evidence. I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache): IN: 2.34969592094s OR: 5.83781504631s Update: (I don't have the source code for the original test, as it was 6 years ago, ...
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Is it possible to change a UIButtons background color?

...s until a web service responds. Must I change to highlight colour on press and have a timer change to disabled colour while waiting for the ws to respond? If I am missing the point can someone please explain. Thanks Polly. – Polly Aug 11 '12 at 11:05 ...
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How do I send a file as an email attachment using Linux command line?

... that uses mysqldump to back up each of my MySQL databases to .sql files and packages them together as a compressed .tar file. The next step I want to accomplish is to send that tar file through email to a remote email server for safekeeping. I've been able to send the raw script in the body an ...
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What's the simplest way to test whether a number is a power of 2 in C++?

...will want to check for it explicitly. http://www.graphics.stanford.edu/~seander/bithacks.html has a large collection of clever bit-twiddling algorithms, including this one. share | improve this ans...
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Which exception should I raise on bad/illegal argument combinations in Python?

...tion.. def import_to_orm(name, save=False, recurse=False): if recurse and not save: raise ValueError("save must be True if recurse is True") There's really no point in doing class BadValueError(ValueError):pass - your custom class is identical in use to ValueError, so why not use that...
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How to compare a local git branch with its remote branch?

How can I see the diff between a local branch and a remote branch? 22 Answers 22 ...
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How to open an elevated cmd using command line for Windows?

How do I open a elevated command prompt using command lines on a normal cmd? 22 Answers ...
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What is phtml, and when should I use a .phtml extension rather than .php?

I'm wondering what the difference between .phtml and .php files is, and when to use one over the other. 6 Answers ...
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C# - how to determine whether a Type is a number

...Byte, SByte, Int16, UInt16, Int32, UInt32, Int64, UInt64, Char, Double,and Single. Taking Guillaume's solution a little further: public static bool IsNumericType(this object o) { switch (Type.GetTypeCode(o.GetType())) { case TypeCode.Byte: case TypeCode.SByte: case Typ...