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Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
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Possible to do a MySQL foreign key to one of two possible tables?
...an be inside of regions, states can be inside of regions. Regions are the top of the food chain.
5 Answers
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Automatic post-registration user authentication
...re building a business app from the ground up in Symfony 2, and I've run into a bit of a snag with the user registration flow: after the user creates an account, they should be automatically logged in with those credentials, instead of being immediately forced to provide their credentials again.
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Opening the Settings app from another app
...openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];
Prior to iOS 8:
You can not. As you said this has been covered many times and that pop up asking you to turn on location services is supplied by Apple and not by the App itself. That is why it is able to the open the settings appl...
Converting datetime.date to UTC timestamp in Python
I am dealing with dates in Python and I need to convert them to UTC timestamps to be used
inside Javascript. The following code does not work:
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Comparing Dates in Oracle SQL
I'm trying to get it to display the number of employees that are hired after June 20, 1994,
But I get an error saying "JUN' invalid identifier. Please help, thanks!
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What's the easiest way to escape HTML in Python?
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cgi.escape is fine. It escapes:
< to &lt;
> to &gt;
& to &amp;
That is enough for all HTML.
EDIT: If you have non-ascii chars you also want to escape, for inclusion in another encoded document that uses a different encoding, like Craig s...
How do I create a nice-looking DMG for Mac OS X using command-line tools?
I need to create a nice installer for a Mac application. I want it to be a disk image (DMG), with a predefined size, layout and background image.
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Is null an Object?
...ullPointerException.
And this is what the Java Language Specification has to say on this topic:
There is also a special null type, the
type of the expression null, which has
no name. Because the null type has no
name, it is impossible to declare a
variable of the null type or to cast
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Structure padding and packing
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Padding aligns structure members to "natural" address boundaries - say, int members would have offsets, which are mod(4) == 0 on 32-bit platform. Padding is on by default. It inserts the following "gaps" into your first structure:
struct mystruct_A {
ch...