How to check the value of a regular expression that came from the server?

Question

JavaScript

Good afternoon!
How to check the value of a regular expression that came from the server? As I understand it, you need to convert the string to a regular expression. I tried to check the expression through the test method, but I get the error Uncaught SyntaxError: Unexpected token ^ , I understand that I need to escape, but the regular expression does not work.
Pattern:"^\d{5}$"

var re = /^\d{5}$/;
if (re.test( "4" ) ) {
  alert("Данная строка соответсвует заявленому патерну");
}

Answer 1

new Regexp() to the rescue