Objects in JavaScript
JavaScript is an object oriented language but most people don't make use of the object oriented features of it except in passing. JavaScript uses a mixed object model in that it has some primitives as well as objects. JavaScript has five primitive types:
- undefined
- null
- boolean
- string
- number
Of these five, only two are what we would expect to be an object anyway. The other three, boolean, string, and number all have wrapped versions, which are objects: Boolean, String, and Number. They are distinguished by starting with uppercase. This is the same sort of model used by Java, a hybrid of objects and primitives.
JavaScript will also box and unbox the primitives as needed.
In this code you can see the boxed and unboxed versions of JavaScript ...
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