`std::collections::BTreeMap<u128, T>` 没有实现 `parity_scale_codec::Encode` 特性

Question

这是我的结构：

#[derive(PartialEq, Eq, PartialOrd, Ord, Default, Clone, Encode, Decode, TypeInfo)]
#[cfg_attr(feature = "std", derive(Debug))]
pub struct SortitionSumTree<AccountId> {
    pub k: u128,
    pub stack: Vec<u128>,
    pub nodes: Vec<u128>,
    pub ids_to_tree_indexes: BTreeMap<AccountId, u128>,
    pub node_indexes_to_ids: BTreeMap<u128, AccountId>,
}

我的存储：

#[pallet::storage]
#[pallet::getter(fn sortition_sum_trees)]
pub type SortitionSumTrees<T> = StorageMap<_, Blake2_128Concat, Vec<u8>, SortitionSumTree<T>>;

但它给出了错误：

该特征parity_scale_codec::Encode未实现std::collections::BTreeMap<u128, T>

Answer 1

你需要使用这个：

#[pallet::getter(fn sortition_sum_trees)]
pub type SortitionSumTrees<T> = StorageMap<
  _, 
  Blake2_128Concat,
  Vec<u8>,
  SortitionSumTree<T::AccountId>
>;

确保在 中使用T::AccountIdSortitionSumTree<T::AccountId>。