原文:https://www.educative.io/edpresso/what-are-traits-in-rust
-------------------------------------------
A trait in Rust is a group of methods that are defined for a particular ...……
第一段示例代码fn main() { let mut l: amp;amp;amp;str; let str1 = String::from(amp;quot;abcamp;quot;); { let str2 = String::from(amp;quot;1234amp;quot;); l = longest ...……