Replace <a> Tag

/* Write a JavaScript function replaceATag(str) that replaces in a HTML document given as string
 all the tags <a href="…">…</a> with corresponding tags [URL=…]…/URL]. Write JS program aTagReplacer.js
 that invokes your function with the sample input data below and prints the output at the console. */

"use strict";

function replaceATag(str) {
    var pattern = /<a\s([^>]+)>([^<]+)<\/a>/g;
    var matcher = pattern.exec(str);
    var replacedString = '[URL ' + matcher[1] + ']' + matcher[2] + '[/URL]';
    console.log(str.replace(matcher[0], replacedString));
}

replaceATag(
    "<ul>" +
    "<li>" +
    "<a href = http://softuni.bg>SoftUni</a>" +
    "</li>" +
    "</ul>");