How Does JavaScript\'s `const` Keyword Handle Object and Array Modifications?

Understanding the Constant Behavior in JavaScript

JavaScript's ES6 standard introduces the const keyword for declaring constants. While it explicitly prohibits reassigning or redeclaring a constant, it allows for modifications to objects and arrays that are referenced by constants.

According to the ES6 specification, "The value of a constant cannot change through re-assignment, and a constant cannot be re-declared." This implies that attempting to change the value of a constant by directly assigning it a new value will not be successful.

However, in the case of objects and arrays, JavaScript's object-based nature comes into play. When you create a constant object or array, you are essentially creating a reference to that object in memory. The const keyword protects this reference from being changed, not the contents of the object or array.

Therefore, operations like yyy.push(6) and yyy.push(1) do not violate the const restriction because they are not modifying the reference to the array yyy. Instead, they are adding and removing elements from the array, which is a valid operation on objects.

In summary, while constants in JavaScript prevent reassigning or redeclaring the reference to an object or array, they allow for modifications to the contents of those objects and arrays. This behavior arises from JavaScript's object-based nature, where constant references do not restrict content modifications.

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