What is the Unconventional Role of the \' Sign\' in \' New Date\'?

Unraveling the Enigmatic Plus Sign in ' new Date'

In the realm of programming, the ' ' sign often symbolizes addition. However, its application in the 'new Date' function presents a puzzle. This article delves into the enigmatic role of the plus sign in this particular context.

The Function in Question

The function in question is:

function fn() {
  return +new Date;
}

As you have noticed, the addition operator ' ' is prefixed to the expression 'new Date'.

The Unary Operator

Unlike its usual role in adding two operands, the ' ' sign here acts as a unary operator. In JavaScript, the unary ' ' operator coerces the following operand into a numerical value.

Coercing to a Number

In the expression ' new Date', the unary ' ' operator coerces the result of 'new Date' into a number. This effectively converts the Date object into a timestamp.

Equivalent Code

The syntax ' new Date' is functionally equivalent to:

Number(new Date)

By explicitly casting the Date object to a number, the operator ensures that the function returns a numerical representation of the current timestamp rather than a Date object.

Conclusion

The ' ' sign in ' new Date' serves as a unary operator, coercing the result of 'new Date' into a numerical value. This operation converts the Date object into a timestamp, allowing the function to return a number representing the current time. Understanding the distinct nature of the unary ' ' operator empowers developers to harness its capabilities effectively in their code.

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