code: function ImmutableCoreModelCacheQueryId (args) {
      // store args
      this.cache = args.cache
      this.query = args.query
      // get list of id(s) being queried
      this.ids = Array.isArray(this.query.select.args.where.id)
          ? this.query.select.args.where.id
          : [this.query.select.args.where.id]
      // number of ids
      this.numIds = this.ids.length
      // get cache keys
      this.idCacheKeys = _.map(this.ids, id => this.cacheKey(id))
      // list of results loaded from cache
      this.cached = []
  }
docs: @function ImmutableCoreModelCacheQueryId
  
  instantiate new ImmutableCoreModelCacheQueryId instance
  
  @param {object} args
  @param {ImmutableCoreModelCache} args.cache
  @param {ImmutableCoreModelQuery} args.query
  
  @returns {ImmutableCoreModelCache}