How to use the jsdoctypeparser.Parser function in jsdoctypeparser

function _parseDocType(typeString) {
    var parser = new TypeParser();
    var node;
    try {
        node = parser.parse(typeString);
        node.valid = true;
    } catch (e) {
        node = {};
        node.error = e.message;
        node.valid = false;
    }
    return node;
}

exports.parseTagTypes = function(str, tag) {
  if (!str) {
    if(tag) {
      tag.types = [];
      tag.typesDescription = "";
      tag.optional = tag.nullable = tag.nonNullable = tag.variable = false;
    }
    return [];
  }
  var Parser = require('jsdoctypeparser').Parser;
  var Builder = require('jsdoctypeparser').Builder;
  var result = new Parser().parse(str.substr(1, str.length - 2));

  var types = (function transform(type) {
    if(type instanceof Builder.TypeUnion) {
      return type.types.map(transform);
    } else if(type instanceof Builder.TypeName) {
      return type.name;
    } else if(type instanceof Builder.RecordType) {
      return type.entries.reduce(function(obj, entry) {
        obj[entry.name] = transform(entry.typeUnion);
        return obj;
      }, {});
    } else {
      return type.toString();
    }
  }(result));