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Mongo: find items that don't have a certain field
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@Theo: Starting from MongoDB 2.0 $exists is able to use indexes (jira.mongodb.org/browse/SERVER-393)
– Dmitry Schetnikovich
Nov 23 '11 at 15:48
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Returning a value from thread?
... on how do you want to create the thread and available .NET version:
.NET 2.0+:
A) You can create the Thread object directly. In this case you could use "closure" - declare variable and capture it using lambda-expression:
object result = null;
Thread thread = new System.Threading.Thread(() => ...
Change string color with NSAttributedString?
...et paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineSpacing = 2.0
// Note: UIFont(appFontFamily:ofSize:) is extended init.
let regularAttributes: [NSAttributedString.Key : Any] = [.font : UIFont(appFontFamily: .regular, ofSize: 15)!, .paragraphStyle : paragraphStyle]
let boldAttrib...
Can't use modulus on doubles?
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#include <cmath>
int main()
{
double x = 6.3;
double y = 2.0;
double z = std::fmod(x,y);
}
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Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?
... has already mentioned, you can safely cast to Exception in .NET Framework 2.0 and higher if RuntimeCompatibilityAttribute(WrapNonExceptionThrows=true) has been applied to your assembly (will be added automatically by the C# and VB compilers).
When this attribute has been applied, non-Exception "...
Send POST request using NSURLSession
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Swift 2.0 solution is here:
let urlStr = “http://url_to_manage_post_requests”
let url = NSURL(string: urlStr)
let request: NSMutableURLRequest =
NSMutableURLRequest(URL: url!) request.HTTPMethod = "POST"
request.setValu...
When should I use Debug.Assert()?
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In Debugging Microsoft .NET 2.0 Applications John Robbins has a big section on assertions. His main points are:
Assert liberally. You can never have too many assertions.
Assertions don't replace exceptions. Exceptions cover the things your code demand...
jQuery $(document).ready and UpdatePanels?
...troduced the on() API) was newly released. With jQuery 1.9 already out and 2.0 in beta being prepared for release, it is a good idea to avoid using delegate() in any new code.
– Dan Herbert
Feb 7 '13 at 1:51
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Ruby: Can I write multi-line string with no concatenation?
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In ruby 2.0 you can now just use %
For example:
SQL = %{
SELECT user, name
FROM users
WHERE users.id = #{var}
LIMIT #{var2}
}
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How efficient is locking an unlocked mutex? What is the cost of a mutex?
...ens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (in the case that the mutex...