enum2pos

enum2pos 是一个用于枚举的 Rust derive 宏，它生成 from_index(usize, Vec<String>) -> Option<Self> 和 to_index() 方法，用于在枚举的变体及其声明中的位置（类似于索引）之间进行转换。

使用方法

将以下内容添加到您的 Cargo.toml

enum2pos = "0.1.1"

示例

use enum2pos::EnumIndex;

#[derive(EnumIndex, PartialEq, Debug)]
enum SampleEnum {
    Unit,
    Unnamed(i32, String),
}

#[test]
fn to_index() {
    let unit = SampleEnum::Unit;
    let unnamed = SampleEnum::Unnamed(42, String::from("test"));

    assert_eq!(unit.to_index(), 0);
    assert_eq!(unnamed.to_index(), 1);
}

#[test]
fn from_index_unit() {
    let index = 0;
    let args: Vec<String> = vec![];
    let expected = Some(SampleEnum::Unit);

    assert_eq!(SampleEnum::from_index(index, &args), expected);
}

#[test]
fn from_index_unnamed() {
    let index = 1;
    let args = vec!["42".to_string(), "test".to_string()];
    let expected = Some(SampleEnum::Unnamed(42, String::from("test")));

    assert_eq!(SampleEnum::from_index(index, &args), expected);
}

#[test]
fn from_index_invalid() {
    let index = 2;
    let args: Vec<String> = vec![];

    assert_eq!(SampleEnum::from_index(index, &args), None);
}