Nullary constructor

In computer programming, a nullary constructor is a constructor that takes no arguments. Also known as a 0-argument constructor or no-argument constructors.

In object-oriented programming, a constructor is code that is run when an object is created. Default constructors of objects are usually nullary.

In algebraic data types, a constructor is one of many tags that wrap data. If a constructor does not take any data arguments, it is nullary.

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