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Create instance of generic type in Java?

...type information is available via reflection. e.g., public abstract class Foo<E> { public E instance; public Foo() throws Exception { instance = ((Class)((ParameterizedType)this.getClass(). getGenericSuperclass()).getActualTypeArguments()[0]).newInstance(); ... } } ...
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How to create enum like type in TypeScript?

...elease) you can use the enum definition like this: enum TShirtSize {   Small,   Medium,   Large } var mySize = TShirtSize.Large; By default, these enumerations will be assigned 0, 1 and 2 respectively. If you want to explicitly set these numbers, you can do so as part of the enum declaration....
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How to profile methods in Scala?

What is a standard way of profiling Scala method calls? 12 Answers 12 ...
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Check if a variable is a string in JavaScript

...ing both typeof and instanceof feels like good advice if your code may be called by others'. @MarkAmery's postmessage edge case matters if you're asking "what was I just postmessaged?" - but you'd expect that to be handled at the interface and not allowed to propagate. Elsewhere, it seems correct t...
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Performance difference between IIf() and If

..."Hello") ' Usage 2 Dim foo = If(result, "Alternative") The first is basically C#'s ternary conditional operator and the second is its coalesce operator (return result unless it’s Nothing, in which case return "Alternative"). If has thus replaced IIf and the latter is obsolete. Like in C#, VB's ...
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#pragma once vs include guards? [duplicate]

... time but #pragma once is very well supported across compilers but not actually part of the standard. The preprocessor may be a little faster with it as it is more simple to understand your exact intent. #pragma once is less prone to making mistakes and it is less code to type. To speed up compil...
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How to use base class's constructors and assignment operator in C++?

... You can explicitly call constructors and assignment operators: class Base { //... public: Base(const Base&) { /*...*/ } Base& operator=(const Base&) { /*...*/ } }; class Derived : public Base { int additional_; public: ...
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How to use Elasticsearch with MongoDB?

... instance. Make sure everything is up to date. sudo apt-get update Install NodeJS. sudo apt-get install nodejs sudo apt-get install npm Install MongoDB - These steps are straight from MongoDB docs. Choose whatever version you're comfortable with. I'm sticking with v2.4.9 because it seems to b...
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Why can't the C# constructor infer type?

...type inference? No. When you have new Foo(bar) then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
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Negative matching using grep (match lines that do not contain foo)

...t, the following may be what you're looking for grep "" /dev/null * | grep foo | grep -v bar | cut -d: -f1 | sort -u (why the first grep?, there's always a way :)) – Motti Oct 25 '17 at 7:18 ...