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Best way to give a variable a default value (simulate Perl ||, ||= )

... In PHP 7 we finally have a way to do this elegantly. It is called the Null coalescing operator. You can use it like this: $name = $_GET['name'] ?? 'john doe'; This is equivalent to $name = isset($_GET['name']) ? $_GET['name']:'john doe'...
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How to override the copy/deepcopy operations for a Python object?

...ully, but this is the first time I've actually gone about overloading the __copy__ and __deepcopy__ methods. I've already Googled around and looked through the built-in Python modules to look for instances of the __copy__ and __deepcopy__ functions (e.g. sets.py , decimal.py , and fracti...
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What is the relative performance difference of if/else versus switch statement in Java?

...ic interface Action { void execute(String input); } And get hold of all implementations in some Map. You can do this either statically or dynamically: Map<String, Action> actions = new HashMap<String, Action>(); Finally replace the if/else or switch by something like this (leav...
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Difference between Repository and Service Layer?

... bool Delete(int id); T Get(int id); bool SaveChanges(); } and call Get(id). Repository layer exposes basic CRUD operations. Service layer exposes business logic, which uses repository. Example service could look like: public interface IUserService { User GetByUserName(string userNa...
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How do you default a new class to public when creating it in Visual Studio?

...1033. Visual Studio 2010 (10.0) and below: There is a zip file in there called Class.zip. Unpack this, edit the file to put in your public keyword then re-pack it (make sure you backup the original). After this, make sure VS rebuilds it's cache (which is just the zipfiles unzipped into directorie...
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How to call another controller Action From a controller in Mvc

I need to call a controller B action FileUploadMsgView from Controller A and need to pass a parameter for it. 10 Answers ...
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Confused about __str__ on list in Python [duplicate]

Coming from a Java background, I understand that __str__ is something like a Python version of toString (while I do realize that Python is the older language). ...
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How to round a number to significant figures in Python

... round_sig = lambda f,p: float(('%.' + str(p) + 'e') % f) allows you to adjust the number of significant digits! – denizb Aug 6 '17 at 22:43 ...
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Why does setTimeout() “break” for large millisecond delay values?

...s due to setTimeout using a 32 bit int to store the delay so the max value allowed would be 2147483647 if you try 2147483648 you get your problem occurring. I can only presume this is causing some form of internal exception in the JS Engine and causing the function to fire immediately rathe...
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Can I use require(“path”).join to safely concatenate urls?

... takes any number. So depending on what you're doing you may need to nest calls, eg.. url.resolve(url.resolve(SERVER_URL, pagePath), queryString) – Molomby Aug 23 '19 at 0:31 ...