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What do two question marks together mean in C#?
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It's the null coalescing operator, and quite like the ternary (immediate-if) operator. See also ?? Operator - MSDN.
FormsAuth = formsAuth ?? new FormsAuthenticationWrapper();
expands to:
FormsAuth = formsAuth != null ? fo...
Swift and mutating struct
There is something that I don't entirely understand when it comes to mutating value types in Swift.
7 Answers
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Protect .NET code from reverse engineering?
Obfuscation is one way, but it can't protect from breaking the piracy protection security of the application. How do I make sure that the application is not tampered with, and how do I make sure that the registration mechanism can't be reverse engineered?
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What are the differences between virtual memory and physical memory?
I am often confused with the concept of virtualization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process?
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Why do you need to invoke an anonymous function on the same line?
...ut closures and saw this everywhere, but there is no clear explanation how it works - everytime I was just told to use it...:
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What to do about a 11000 lines C++ source file?
...) mainmodule.cpp source file in our project and every time I have to touch it I cringe.
34 Answers
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Should I use tag for icons instead of ? [closed]
Facebook's HTML and Twitter Bootstrap HTML (before v3) both use the <i> tag to display icons.
7 Answers
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What is the exact problem with multiple inheritance?
I can see people asking all the time whether multiple inheritance should be included into the next version of C# or Java. C++ folks, who are fortunate enough to have this ability, say that this is like giving someone a rope to eventually hang themselves.
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Big-O for Eight Year Olds? [duplicate]
... operation on a data structure, I understand that the number of operations it has to perform won't grow because there are more items. And an O(n) operation would mean that you would perform a set of operations on each element. Could somebody fill in the blanks here?
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Check synchronously if file/directory exists in Node.js
... fs.existsSync():
const fs = require("fs"); // Or `import fs from "fs";` with ESM
if (fs.existsSync(path)) {
// Do something
}
It was deprecated for several years, but no longer is. From the docs:
Note that fs.exists() is deprecated, but fs.existsSync() is not. (The
callback parameter t...