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jQuery first child of “this”
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I believe find() searches through all descendants, and :first-child can match one element per parent. Hence, this query can is likely to return several elements. Or am I mistaken?
– Jørn Schou-Rode
Feb 16 '10 at 19:38
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How to loop through an array containing objects and access their properties
I want to cycle through the objects contained in an array and change the properties of each one. If I do this:
15 Answers
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Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...e main point. Even if you use empty array or empty list, those are objects and they are stored in memory. Than Garbage Collector has to take care of them. If you are dealing with high throughput application, it could be noticeable impact.
Enumerable.Empty does not create an object per call thus put...
How do I use $rootScope in Angular to store variables?
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Notice that the rootScope's variable is set when the module initializes, and then each of the inherited scope's get their own copy which can be set independently (the change function). Also, the rootScope's value can be updated too (the changeRs function in myCtrl2)
angular.module('myApp', [])
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SharedPreferences.onSharedPreferenceChangeListener not being called consistently
..., but eventually, will get garbage collected, removed from the WeakHashMap and stop working.
Keep a reference to the listener in a field of your class and you will be OK, provided your class instance is not destroyed.
i.e. instead of:
prefs.registerOnSharedPreferenceChangeListener(
new SharedPr...
How to detect when an Android app goes to the background and come back to the foreground
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The onPause() and onResume() methods are called when the application is brought to the background and into the foreground again. However, they are also called when the application is started for the first time and before it is killed. You ...
Why doesn't django's model.save() call full_clean()?
...matic" validation option which is both simple enough to actually be useful and robust enough to handle all the edge cases is -- if it's even possible -- far more than can be accomplished on the 1.2 timeframe. Hence, for now, Django doesn't have any such thing, and won't have it in 1.2. If you think ...
How to export all collections in MongoDB?
I want to export all collections in MongoDB by the command:
26 Answers
26
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If strings are immutable in .NET, then why does Substring take O(n) time?
... liked this question so much, I just blogged it. See Strings, immutability and persistence
The short answer is: O(n) is O(1) if n does not grow large. Most people extract tiny substrings from tiny strings, so how the complexity grows asymptotically is completely irrelevant.
The long answer is:
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How do I activate C++ 11 in CMake?
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CMake 3.1 introduced the CMAKE_CXX_STANDARD variable that you can use. If you know that you will always have CMake 3.1 available, you can just write this in your top-level CMakeLists.txt file, or put it right before any new target is defined:
set (CMAKE_CXX_ST...