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Why do people use __(double underscore) so much in C++
I was having a look through some open source C++ code and notice a lot of double under scores where used in the code, mainly at the start of variable names.
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Visual Studio SP1 error: silverlight_sdk.msi is unavailable
...ying to install the SP1 for Visual Studio 2010. I first installed the beta and it worked fine. Then I used the web platform installer to install the SQL CE Compact 4, which I assume installed the full SP1 after (this installation took over 12 hours, so I canceled it). The web platform installer told...
Real mouse position in canvas [duplicate]
....clientY - rect.top
};
}
Just call it from your event with the event and canvas as arguments. It returns an object with x and y for the mouse positions.
As the mouse position you are getting is relative to the client window you'll have to subtract the position of the canvas element to convert...
How to add property to a class dynamically?
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I suppose I should expand this answer, now that I'm older and wiser and know what's going on. Better late than never.
You can add a property to a class dynamically. But that's the catch: you have to add it to the class.
>>> class Foo(...
Why can I throw null in Java? [duplicate]
...erException.
In other words, throw checks that its argument is nonnull, and if it is null, it throws a NullPointerException.
JLS 14.18 specifies this behavior:
If evaluation of the Expression completes normally, producing a null value, then an instance V' of class NullPointerException is cre...
Update MongoDB field using value of another field
...ion 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 also introduced the $set pipeline stage operator which is an...
MySQL integer field is returned as string in PHP
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I just did some tests on Windows with Laravel and Mysql on the very same schema and database server. On Windows the primary key is returned as an Integer and on Linux it's a String.
– AturSams
Oct 28 '14 at 15:38
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How do I set up a simple delegate to communicate between two view controllers?
I have two UITableViewControllers and need to pass the value from the child view controller to the parent using a delegate. I know what delegates are and just wanted to see a simple to follow example.
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Formula px to dp, dp to px android
...ing to calculate a variable amount of pixels to density independent pixels and vice-versa.
20 Answers
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Using mixins vs components for code reuse in Facebook React
I'm beginning to use Facebook React in a Backbone project and so far it's going really well.
However, I noticed some duplication creeping into my React code.
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