JavaScript new.target meta Property
The new.target pseudo-property let us detect whether a function or constructor is called with the help of new operator or not.
Syntax:
new.target
The following example demonstrates the meta property.
Example 1: In this example, the function is called without the new operator.
HTML
<!DOCTYPE HTML><html> <body style="text-align:center;"> <h1 style="color:green;"> GeeksForGeeks </h1> <p> JavaScript | new.target metaKey property </p> <button onclick="Geeks();"> click here </button> <p id="GFG_DOWN"></p> <script> var el_down = document .getElementById("GFG_DOWN"); function Fun() { if (!new.target) { throw 'Fun() is called without new operator'; } } function Geeks(event) { try { Fun(); } catch (e) { el_down.innerHTML = e; } } </script></body> </html> |
Output:
Example 2: In this example, the function is called with the new operator.
HTML
<!DOCTYPE HTML><html> <body style="text-align:center;"> <h1 style="color:green;"> GeeksForGeeks </h1> <p> JavaScript | new.target metaKey property </p> <button onclick="Geeks();"> click here </button> <p id="GFG_DOWN"></p> <script> var el_down = document .getElementById("GFG_DOWN"); class Person { constructor(name) { this.name = name; if (!new.target) {throw 'Function is called without new operator'; } else {throw 'Function is called with new operator'; } } } function Geeks(event) { try { var p = new Person('GFG'); } catch (e) { el_down.innerHTML = e; } } </script></body> </html> |
Output:
