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Create array of symbols
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Thanks this is really helpful.
– sonnyhe2002
Dec 18 '16 at 20:40
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Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
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Generically, a covariant type parameter is one which is allowed to vary down as the class is subtyped (alternatively, vary with subtyping, hence the "co-" prefix). More concretely:
trait List[+A]
List[Int] is a subtype of List[A...
Accessing JPEG EXIF rotation data in JavaScript on the client side
... rotation, as set by the camera in JPEG EXIF image data. The trick is that all this should happen in the browser, using JavaScript and <canvas> .
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Count occurrences of a char in plain text file
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If all you need to do is count the number of lines containing your character, this will work:
grep -c 'f' myfile
However, it counts multiple occurrences of 'f' on the same line as a single match.
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How to merge 2 List and removing duplicate values from it in C#
...return set. This is different
behavior to the Concat
method, which returns all the elements
in the input sequences including
duplicates.
List<int> list1 = new List<int> { 1, 12, 12, 5};
List<int> list2 = new List<int> { 12, 5, 7, 9, 1 };
List<int> ulist = list1.Union(l...
Covariance, Invariance and Contravariance explained in plain English?
... say it is used to decide whether a method is overwritten or overloaded.
All of the above.
At heart, these terms describe how the subtype relation is affected by type transformations. That is, if A and B are types, f is a type transformation, and ≤ the subtype relation (i.e. A ≤ B means that ...
Git push results in “Authentication Failed”
...ettings of your Github account. Using this token as your
password should allow you to push to your remote repository via HTTPS.
Use your username as usual.
https://help.github.com/articles/creating-a-personal-access-token-for-the-command-line/
You may also need to update the origin for your r...
jQuery posting JSON
...mple scenarios, but the url-encoded message can be very problematic, especially for arrays of stuff.
– FMM
Sep 17 '12 at 19:14
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Five equal columns in twitter bootstrap
...t;
<div class="span2"></div>
</div>
Voila!
Five equally spaced and centered columns.
In bootstrap 3.0, this code would look like
<div class="row">
<div class="col-md-2 col-md-offset-1"></div>
<div class="col-md-2"></div>
<div c...
Setting action for back button in navigation controller
...; Bool
}
extension UINavigationController {
public func navigationBar(_ navigationBar: UINavigationBar, shouldPop item: UINavigationItem) -> Bool {
// Prevents from a synchronization issue of popping too many navigation items
// and not enough view controllers or viceversa fr...