What Does the \' \' Sign Do in \' new Date\' in JavaScript?

Understanding the Plus Sign in " new Date"

In JavaScript, the " " symbol can be used as a unary operator, which takes a single operand and returns a new value. When used with the "new Date" expression, it transforms the Date object into a timestamp, effectively returning the number of milliseconds since the epoch (January 1, 1970 UTC).

This is equivalent to:

<code class="javascript">function fn() {
    return Number(new Date);
}</code>

The Number() function converts the Date object to a numeric value, which is essentially the timestamp.

You can better understand this behavior by inspecting the following example:

<code class="javascript">console.log(typeof new Date()); // Output: "object"
console.log(typeof +new Date()); // Output: "number"</code>

As you can see, the "new Date()" expression returns an object, but the " " operator converts it into a number, providing you with the timestamp.

In summary, the plus sign ( ) in " new Date" acts as a unary operator, converting the Date object into a numeric timestamp, allowing you to obtain the time elapsed since the epoch.

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