Unescape HTML entities in Javascript?

Question

I have some Javascript code that communicates with an XML-RPC backend. The XML-RPC returns strings of the form:

Answer 1

a javascript solution that catches the common ones:

var map = {amp: '&', lt: '<', gt: '>', quot: '"', '#039': "'"}
str = str.replace(/&([^;]+);/g, (m, c) => map[c])

this is the reverse of https://stackoverflow.com/a/4835406/2738039