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The Object isExtensible() method

Find out all about the JavaScript isExtensible() method of the Object object

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This method checks if we can add new properties to an object.

Any object is extensible, unless it’s been used as an argument to

Usage:

const dog = {}
Object.isExtensible(dog) //true
const cat = {}
Object.freeze(cat)
Object.isExtensible(cat) //false
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