Rust 在柴油塔中使用新类型

我正在使用新类型，如

struct GuildId（i64）用于my diesel模型结构中的列。目前，我正在实施以下特征：

#[derive(Debug, Display, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, serde::Serialize)]
pub struct $name(pub i64);

impl AsExpression<BigInt> for $name { /* delegate to <i64 as AsExpression<BigInt> */ */ }

impl<ST, DB: Backend> Queryable<ST, DB> for $name
where i64: FromSql<ST, DB> { /* also delegate to i64 */

频道
仍不执行
归属于DSL
。当我尝试将其转换为trait时，它无法编译，并显示以下消息：

error[E0277]: the trait bound `diesel::query_builder::select_statement::SelectStatement<webcord_schema::schema::channels::table>: diesel::query_dsl::filter_dsl::FilterDsl<diesel::expression::operators::Eq<webcord_schema::schema::channels::columns::guild_id, &webcord_schema::models::GuildId>>` is not satisfied
  --> src/index/guild.rs:23:32
   |
23 |                 let channels = <models::Channel as BelongingToDsl<&models::Guild>>::belonging_to(&guild)
   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `diesel::query_dsl::filter_dsl::FilterDsl<diesel::expression::operators::Eq<webcord_schema::schema::channels::columns::guild_id, &webcord_schema::models::GuildId>>` is not implemented for `diesel::query_builder::select_statement::SelectStatement<webcord_schema::schema::channels::table>`
   |
   = help: the following implementations were found:
             <diesel::query_builder::select_statement::SelectStatement<F, S, D, W, O, L, Of, G, LC> as diesel::query_dsl::filter_dsl::FilterDsl<Predicate>>
   = note: required because of the requirements on the impl of `diesel::query_dsl::filter_dsl::FilterDsl<diesel::expression::operators::Eq<webcord_schema::schema::channels::columns::guild_id, &webcord_schema::models::GuildId>>` for `webcord_schema::schema::channels::table`

error[E0277]: the trait bound `webcord_schema::models::GuildId: diesel::expression::Expression` is not satisfied
  --> src/index/guild.rs:23:32
   |
23 |                 let channels = <models::Channel as BelongingToDsl<&models::Guild>>::belonging_to(&guild)
   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `diesel::expression::Expression` is not implemented for `webcord_schema::models::GuildId`
   |
   = note: required because of the requirements on the impl of `diesel::expression::Expression` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::expression::AsExpression<diesel::sql_types::BigInt>` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::query_dsl::belonging_to_dsl::BelongingToDsl<&webcord_schema::models::Guild>` for `webcord_schema::models::Channel`

error[E0277]：特性绑定的'diesel:：query\u builder:：select\u语句：：SelectStatement:diesel:：query\u dsl:：filter\u dsl:：FilterDsl'不满足
-->src/index/guild.rs:23:32
|
23 | let channels=：：属于（&guild）
|^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^未为`柴油机：：查询生成器：：选择语句：：选择语句'实现特性`柴油机：：查询dsl：：过滤dsl：：过滤dsl'`
|
=帮助：找到了以下实现：
=注意：之所以需要，是因为对于“webcord\u schema:：schema:：channels:：table”的“diesel:：query\u dsl:：filter\u dsl:：FilterDsl”impl中的要求`
错误[E0277]：未满足特性绑定的'webcord_schema:：models:：Guidid:diesel:：expression:：expression'
-->src/index/guild.rs:23:32
|
23 | let channels=：：属于（&guild）
|^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^未为`
|
=注意：由于“`&webcord_schema:：models:：Guidid”的“diesel:：expression:：expression`impl”上的要求，因此需要`
=注意：由于“&webcord_schema:：models:：Guidid”的“diesel:：expression:：AsExpression”impl中的要求，因此需要此选项`
=注意：由于“webcord\u schema:：models:：Channel”的“diesel:：query\u dsl:：besting\u to\u dsl:：besting todsl”impl中的要求，因此需要`

我缺少哪些特征？
该错误与
归属于DSL
无关，而是与自定义新类型包装器的不完整实现有关

由于错误消息表明您缺少新类型包装器的trait impl：

error[E0277]: the trait bound `webcord_schema::models::GuildId: diesel::expression::Expression` is not satisfied
  --> src/index/guild.rs:23:32
   |
23 |                 let channels = <models::Channel as BelongingToDsl<&models::Guild>>::belonging_to(&guild)
   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `diesel::expression::Expression` is not implemented for `webcord_schema::models::GuildId`
   |
   = note: required because of the requirements on the impl of `diesel::expression::Expression` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::expression::AsExpression<diesel::sql_types::BigInt>` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::query_dsl::belonging_to_dsl::BelongingToDsl<&webcord_schema::models::Guild>` for `webcord_schema::models::Channel`

belovingtodsl
trait需要一个类型参数。我对柴油机没有经验，但可能是柴油机属于柴油机？是的，我忘了放那个。但是它仍然有下面的要求，我更新了错误。很抱歉很长时间没有接受答案。我停止了那个项目的工作，所以我还没有验证你的答案。但是感谢您的努力。

#[sql_type=“diesel:：sql_types:：BigInt”]是和@M.Leonhard上的diesel文档页面缺少的东西。这并不奇怪，因为这两个特征都与此属性无关。是这样的。ToSql和FromSql之间的关系非常密切，他们的文档说要添加

#[派生（AsExpression）]

。但是他们没有说“并且还添加了这个sql类型属性”或“检查AsExpression文档以了解特殊需求”。AsExpression派生错误消息没有说“缺少sql类型属性”。因此，用户很容易错过关键信息，并浪费大量时间搜索解决方案。

error[E0277]: the trait bound `webcord_schema::models::GuildId: diesel::expression::Expression` is not satisfied
  --> src/index/guild.rs:23:32
   |
23 |                 let channels = <models::Channel as BelongingToDsl<&models::Guild>>::belonging_to(&guild)
   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `diesel::expression::Expression` is not implemented for `webcord_schema::models::GuildId`
   |
   = note: required because of the requirements on the impl of `diesel::expression::Expression` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::expression::AsExpression<diesel::sql_types::BigInt>` for `&webcord_schema::models::GuildId`
   = note: required because of the requirements on the impl of `diesel::query_dsl::belonging_to_dsl::BelongingToDsl<&webcord_schema::models::Guild>` for `webcord_schema::models::Channel`