枚举类型别名

Question

有没有办法让代码在下面工作？也就是说，在类型别名下导出一个枚举，并允许以新名称访问这些变体？

enum One { A, B, C } 

type Two = One; 

fn main() { 
    // error: no associated item named `B` found for type `One` in the current scope 
    let b = Two::B; 
} 

Answer 1

我不认为类型别名允许做你想要什么，而是你可以重命名的use声明枚举类型：

enum One { A, B, C } 

fn main() { 
    use One as Two; 
    let b = Two::B; 
} 

您可以结合使用这与pub use重新导出类型在不同的标识符下：

mod foo { 
    pub enum One { A, B, C } 
} 

mod bar { 
    pub use foo::One as Two; 
} 

fn main() { 
    use bar::Two; 
    let b = Two::B; 
} 

mod foo { 
    pub enum One { A, B, C } 
} 

mod bar { 
    pub use foo::One as Two; 
} 

fn main() { 
    use bar::Two; 
    let b = Two::B; 
}