12-泛型函数简写

泛型函数简写 — Rust 语言之旅

内容来源 · Tour of Rust / Rust 语言之旅

原文链接: https://tourofrust.com/85_zh-cn.html

泛型函数简写

Rust 为由 Trait 限制的泛型函数提供了简写形式:

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fn my_function(foo: impl Foo) {
    ...
}

这段代码等价于:

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fn my_function<T>(foo: T)
where
    T:Foo
{
    ...
}

示例代码

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struct SeaCreature {
    pub name: String,
    noise: String,
}

impl SeaCreature {
    pub fn get_sound(&self) -> &str {
        &self.noise
    }
}

trait NoiseMaker {
    fn make_noise(&self);
}

impl NoiseMaker for SeaCreature {
    fn make_noise(&self) {
        println!("{}", &self.get_sound());
    }
}

fn generic_make_noise(creature: &impl NoiseMaker)
{
    // 我们在编译期就已经知道其真实类型
    creature.make_noise();
}

fn main() {
    let creature = SeaCreature {
        name: String::from("Ferris"),
        noise: String::from("咕噜"),
    };
    generic_make_noise(&creature);
}
最后修改 August 21, 2026: 更新 (76fc81a2e)