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What is an optional value in Swift?
...long with Generics) are one of the most difficult Swift concepts to understand. Because of how they are written and used, it's easy to get a wrong idea of what they are. Compare the optional above to creating a normal String:
var name: String = "Bertie" // No "?" after String
From the syntax it loo...
Why would a static nested interface be used in Java?
... above example is redundant (a nested interface is automatically "static") and can be removed with no effect on semantics; I would recommend it be removed. The same goes for "public" on interface methods and "public final" on interface fields - the modifiers are redundant and just add clutter to the...
In C# what is the difference between ToUpper() and ToUpperInvariant()?
In C#, what is the difference between ToUpper() and ToUpperInvariant() ?
6 Answers
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How does cookie based authentication work?
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A cookie is basically just an item in a dictionary. Each item has a key and a value. For authentication, the key could be something like 'username' and the value would be the username. Each time you make a request to a website, your browser will include the cookies in the request, and the host s...
What are the various “Build action” settings in Visual Studio project properties and what do they do
...for each file selected in Solution Explorer. There are a number of options and it's difficult to know what each one of them will do.
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Accessing localhost:port from Android emulator
...ith the IP address "10.0.2.2".
This has been designed in this way by the Android team. So your webserver can perfectly run at localhost and from your Android app you can access it via "http://10.0.2.2:<hostport>".
If your emulator must access the internet through a proxy server, you can con...
When to use ' (or quote) in Lisp?
...ough the major parts of an introductory Lisp book, I still couldn't understand what the special operator (quote) (or equivalent ' ) function does, yet this has been all over Lisp code that I've seen.
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How to mock ConfigurationManager.AppSettings with moq
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I believe one standard approach to this is to use a facade pattern to wrap the configuration manager and then you have something loosely coupled that you have control over.
So you would wrap the ConfigurationManager. Something like:
public...
What is the difference between UNION and UNION ALL?
What is the difference between UNION and UNION ALL ?
26 Answers
26
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mysqli or PDO - what are the pros and cons? [closed]
In our place we're split between using mysqli and PDO for stuff like prepared statements and transaction support. Some projects use one, some the other. There is little realistic likelihood of us ever moving to another RDBMS.
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