下面的代码运行得很好（playground）：

struct MyStruct<const B: bool>;

impl MyStruct<false> {
    pub fn bar() {
        println!("false");
    }
}
impl MyStruct<true> {
    pub fn bar() {
        println!("true");
    }
}

impl MyStruct<false> {
    pub fn foo() {
        MyStruct::<false>::bar()
    }
}
impl MyStruct<true> {
    pub fn foo() {
        MyStruct::<true>::bar()
    }
}

fn main() {
    MyStruct::<false>::foo();
    MyStruct::<true>::foo();
}

字符串
其结果是：

false
true

型
另一方面，这段代码将失败（playground）：

struct MyStruct<const B: bool>;

impl MyStruct<false> {
    pub fn bar() {
        println!("false");
    }
}
impl MyStruct<true> {
    pub fn bar() {
        println!("true");
    }
}

impl<const B: bool> MyStruct<B> {
    pub fn foo() {
        MyStruct::<B>::bar()
    }
}

fn main() {
    MyStruct::<false>::foo();
    MyStruct::<true>::foo();
}

型
导致：

error[E0599]: no function or associated item named `bar` found for struct `MyStruct<B>` in the current scope
  --> src/main.rs:16:24
   |
1  | struct MyStruct<const B: bool>;
   | ------------------------------- function or associated item `bar` not found for this
...
16 |         MyStruct::<B>::bar()
   |                        ^^^ function or associated item not found in `MyStruct<B>`
   |
   = note: the function or associated item was found for
           - `MyStruct<false>`
           - `MyStruct<true>`

型
我可以理解无限值类型的错误，但为什么是布尔类型呢？
有没有办法克服这一点？