不幸的是，没有内置方法可以做到这一点.

Unfortunately there is no built-in way to do this.

格式化语法是由早期Rust使用者采用的功能演变而来的.简洁意味着新功能在事实之后很难添加.

The formatting syntax evolved with features that early Rust adopters needed at the time. Its terseness means that new features are very difficult to add after the fact.