Convert template from Handlebars to Mustache

convertHandlebarsToMustache

function convertToMustache(str) {
  var stack = [],
      reg = /{{([#\/]?)(\w+)?\s?(..\/)?(\w+)?}}/g;
  str = str.replace(reg, function (match, pre, helper, path, key) {
    if (pre === '#') {
      stack.push({
        type: helper,
        key: key
      });
    }
    if (pre === '/') {
      var obj = stack.pop();
      if (obj.type === helper) {
        key = obj.key;
      } else {
        throw new Error('match error');
      }
    }
    if (helper === 'else') {
      var obj = stack[stack.length - 1];
      return '{{/' + obj.key + '}}{{^' + obj.key + '}}';
    }
    key = key || helper;
    return '{{' + pre + key + '}}';
  });
  return str;
}