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Python initializing a list of lists [duplicate]
...
The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the sam...
Changes in import statement python3
...a single function. In Python 2 you were permitted to be semi-lazy:
def sin_degrees(x):
from math import *
return sin(degrees(x))
Note that it already triggers a warning in Python 2:
a.py:1: SyntaxWarning: import * only allowed at module level
def sin_degrees(x):
In modern Python 2 co...
ASP.NET MVC: Is Controller created for every request?
...ther controller.
The short version is that ControllerActivator.Create is called (for every request) to create a Controller (which inits a new Controller either through the DependencyResolver or through the Activator if no Resolver has been set up):
public IController Create(RequestContext requestC...
Performing Inserts and Updates with Dapper
...Connection extension methods:
T Get<T>(id);
IEnumerable<T> GetAll<T>();
int Insert<T>(T obj);
int Insert<T>(Enumerable<T> list);
bool Update<T>(T obj);
bool Update<T>(Enumerable<T> list);
bool Delete<T>(T obj);
bool Delete<T>(Enumera...
Design Patterns: Factory vs Factory method vs Abstract Factory
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All three Factory types do the same thing: They are a "smart constructor".
Let's say you want to be able to create two kinds of Fruit: Apple and Orange.
Factory
Factory is "fixed", in that you have just one implementation ...
Align image in center and middle within div
...00%; height:100%">
<img src="http://www.garcard.com/images/garcard_symbol.png">
</div>
JSFiddle
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How do I shuffle an array in Swift?
...Distance` in < Swift 4.1
let d: Int = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
let i = index(firstUnshuffled, offsetBy: d)
swapAt(firstUnshuffled, i)
}
}
}
extension Sequence {
/// Returns an array with the contents of this...
What's the point of map in Haskell, when there is fmap?
...make an answer to draw attention to augustss's comment:
That's not actually how it happens. What happened was that the type of map was generalized to cover Functor in Haskell 1.3. I.e., in Haskell 1.3 fmap was called map. This change was then reverted in Haskell 1.4 and fmap was introduced. The ...
Amazon S3 CORS (Cross-Origin Resource Sharing) and Firefox cross-domain font loading
...irefox not loading font from different origin than the current webpage. Usually, the issue arise when the fonts are served on CDNs.
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Integrating the ZXing library directly into my Android application
...de so it hopefully can help others with the same problem as I had ;)
Install Apache Ant - (See this YouTube video for config help)
Download the ZXing source from ZXing homepage and extract it
With the use of Windows Commandline (Run->CMD) navigate to the root directory of the downloaded zxing s...