code: function tryRequire(name, def, isRoot) {
      function _require() {
          if (!is_1.isNode())
              /* istanbul ignore next */
              return to_1.toDefault(null, def);
          if (isRoot)
              return require.main.require(name);
          return require(name);
      }
      return tryWrap(_require)(def);
  }
docs: Try Require
  Tries to require a module returns null
  if cannot require or empty object.
  
  @param name the name of module to try and require.
  @param def optional default value on null.
  @param isRoot used internally by tryRootRequire to require root modules.