haraka-plugin-webmailer/templater.js

let escape = require("lodash.escape");

module.exports = function(strings) {
  //first element is the strings, don't need it
  let args = Array.prototype.slice.call(arguments,1);

  //first element will be the initial value
  return strings.reduce(function(result, string, i) {
    return result + escape(args[i-1]) + string;
  });
};