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Why is a pure virtual function initialized by 0?

...dn't think he could get another keyword, such as "pure" past the C++ community at the time the feature was being implemented. This is described in his book, The Design & Evolution of C++, section 13.2.3: The curious =0 syntax was chosen ... because at the time I saw no chance of getting ...
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Why do you use typedef when declaring an enum in C++?

I haven't written any C++ in years and now I'm trying to get back into it. I then ran across this and thought about giving up: ...
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How do I fix PyDev “Undefined variable from import” errors?

...a settings object. I import that in module b and assign an attribute with: 13 Answers ...
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FileSystemWatcher vs polling to watch for file changes

...e system watcher fail in production and test environments. I now consider it a convenience, but I do not consider it reliable. My pattern has been to watch for changes with the files system watcher, but poll occasionally to catch missing file changes. Edit: If you have a UI, you can also give y...
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How do I run a node.js app as a background service?

... Copying my own answer from How do I run a Node.js application as its own process? 2015 answer: nearly every Linux distro comes with systemd, which means forever, monit, PM2, etc are no longer necessary - your OS already handles these tasks. Make a myapp.service file (replacing 'myapp' w...
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When to use static vs instantiated classes

PHP is my first programming language. I can't quite wrap my head around when to use static classes vs instantiated objects. ...
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Is if(items != null) superfluous before foreach(T item in items)?

... You still need to check if (items != null) otherwise you will get NullReferenceException. However you can do something like this: List<string> items = null; foreach (var item in items ?? new List<string>()) { item.Dump(); } but you...
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Importing CSV with line breaks in Excel 2007

... behave differently depending on whether a CSV file is imported by opening it from the File->Open menu or by double-clicking on the file in Explorer. I have a CSV file that is in UTF-8 encoding and contains newlines in some cells. If I open this file from Excel's File->Open menu, the "import ...
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What is the most robust way to force a UIView to redraw?

I have a UITableView with a list of items. Selecting an item pushes a viewController that then proceeds to do the following. from method viewDidLoad I fire off a URLRequest for data that is required by on of my subviews - a UIView subclass with drawRect overridden. When the data arrives from the clo...
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Constant Amortized Time

What is meant by "Constant Amortized Time" when talking about time complexity of an algorithm? 6 Answers ...