code: function create (spec) {
    const manager = {
      store: {}
    }
  
    manager.getStore = getStore.bind(null, manager)
    manager.clear = clear.bind(null, manager)
    manager.get = get.bind(null, manager, spec.errorInfoCbGet)
    manager.add = add.bind(null, manager, spec.errorInfoCbAdd)
  
    return manager
  }
docs: create instance
  @param {Object} spec
  @return {Object}