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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, ...
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 ...
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.
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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...
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...
