2.2.2.9 TryFrom 与 TryInto
09-TryFrom 与 TryInto — Comprehensive Rust
译文 · 基于 Comprehensive Rust
原文链接: https://google.github.io/comprehensive-rust/idiomatic/foundations-api-design/predictable-api/common-traits/try-from-into.html
2.2.2.9 TryFrom 与 TryInto
从一种类型到另一种类型的可失败转换。
可派生：❌
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| // Copyright 2025 Google LLC
// SPDX-License-Identifier: Apache-2.0
#[derive(Debug)]
pub struct InvalidNumber;
#[derive(Debug)]
pub struct DivisibleByTwo(usize);
impl TryFrom<usize> for DivisibleByTwo {
type Error = InvalidNumber;
fn try_from(value: usize) -> Result<Self, InvalidNumber> {
if value.rem_euclid(2) == 0 {
Ok(DivisibleByTwo(value))
} else {
Err(InvalidNumber)
}
}
}
fn main() {
let success: Result<DivisibleByTwo, _> = 4.try_into();
dbg!(success);
let fail: Result<DivisibleByTwo, _> = 5.try_into();
dbg!(fail);
}
|