Why Do Identical JavaScript Objects Fail Equality Checks?

Unveiling the Mystery: Why Objects of Identical Properties Fail Equality Checks

In the realm of JavaScript, the equality operators (== and ===) appear to behave unexpectedly when comparing objects with identical properties. This anomaly stems from the fundamental principles of object comparison in JavaScript.

Consider the following code:

var a = {};
var b = {};

console.log(a == b); // returns false
console.log(a === b); // returns false

Intriguingly, even though the objects 'a' and 'b' possess identical properties, the equality checks yield false. This behavior seems counterintuitive, as one might expect objects with identical properties to be considered equal.

To understand this phenomenon, it's crucial to recognize the difference between regular (==) and strict (===) equality. While strict equality (===) disables type conversion, object comparisons in both cases evaluate to true only when the exact same object is compared.

In other words, regardless of the type of equality operator used, the principle remains the same: objects are equal only if they refer to the same exact instance. Therefore, two distinct objects with identical properties (like 'a' and 'b' in our example) will never be equal in the eyes of JavaScript.

If it becomes necessary to ascertain the equality of an object's properties, consider seeking alternative approaches, such as traversing the objects and comparing their property values one by one.

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