Trait GraphQLField 

pub trait GraphQLField: Send + Sync {
    // Required method
    fn resolve<'life0, 'async_trait>(
        &'life0 self,
        req: FieldRequest,
    ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
}

富 resolver trait：可访问字段参数与嵌套 selection（经 GraphQLSchema::query_field / GraphQLSchema::mutation_field 注册）。 async fn in trait 非 dyn-compatible，故用 #async_trait 换取对象安全 （可存入 FieldHandler::Rich 的 Arc<dyn GraphQLField>）。

Required Methods

fn resolve<'life0, 'async_trait>( &'life0 self, req: FieldRequest, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors