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When would you use a WeakHashMap or a WeakReference?
...th user-supplied images, like the
web site design tool I work on.
Naturally you want to cache these
images, because loading them from disk
is very expensive and you want to
avoid the possibility of having two
copies of the (potentially gigantic)
image in memory at once.
Because an...
Is there a performance impact when calling ToList()?
...on) constructor. This constructor must make a copy of the array (more generally IEnumerable<T>), otherwise future modifications of the original array will change on the source T[] also which wouldn't be desirable generally.
I would like to reiterate this will only make a difference with a hu...
What integer hash function are good that accepts an integer hash key?
...mple) and has no common factors with it. This way the hash function covers all your hash space uniformly.
Edit: The biggest disadvantage of this hash function is that it preserves divisibility, so if your integers are all divisible by 2 or by 4 (which is not uncommon), their hashes will be too. Thi...
Parse string to DateTime in C#
...teTime.Parse() will try figure out the format of the given date, and it usually does a good job. If you can guarantee dates will always be in a given format then you can use ParseExact():
string s = "2011-03-21 13:26";
DateTime dt =
DateTime.ParseExact(s, "yyyy-MM-dd HH:mm", CultureInfo.Invar...
Custom fonts in iOS 7
...
First of all I'm assuming that SpriteKit doesn't make any difference.
You need your font in .otf or .ttf copied to your project. For example in Supporting Files.
You need to edit .plist file. Add "Fonts provided by application" key ...
How to parse a string to an int in C++?
...g. ss << std::hex) before trying the conversion. But this means the caller must know a priori what base the number is -- and how can the caller possibly know that? The caller doesn't know what the number is yet. They don't even know that it is a number! How can they be expected to know what ba...
How can I disable a button in a jQuery dialog from a function?
...tinue" button. I would like this "continue" button to only be enabled once all the fields have content in them, else it will remain disabled.
...
How do you clone an Array of Objects in Javascript?
...
The issue with your shallow copy is that all the objects aren't cloned. While the references to each object are unique in each array, once you ultimately grab onto it you're dealing with the same object as before. There is nothing wrong with the...
How to select the first element with a specific attribute using XPath
...
This will get all books from 'US'. (/bookstore/book[@location='US'])[1] will get the first one.
– Kevin Driedger
Apr 17 '12 at 19:39
...
Maximum and Minimum values for ints
...on doesn't apply. The plain int type is unbounded.
However, you might actually be looking for information about the current interpreter's word size, which will be the same as the machine's word size in most cases. That information is still available in Python 3 as sys.maxsize, which is the maximum ...