amass

自动为嵌套枚举生成 From 实现，甚至跨crate。

只需要对每个嵌套枚举应用一个属性。

示例

pub mod letter {
    pub struct A;
    pub struct B;
    pub struct C;

    #[amass::amass_telety(crate::letter)]
    pub enum Letter {
        A(A),
        B(B),
        C(C),
    }
}

pub mod number {
    pub struct One;
    pub struct Two;
    pub struct Three;

    #[amass::amass_telety(crate::number)]
    pub enum Number {
        One(One),
        Two(Two),
        Three(Three),
    }
}

use letter::Letter;
use number::Number;

#[amass::amass_telety(crate)]
pub enum Alphanumeric {
    Letter(Letter),
    Number(Number),
}

pub struct Underscore;

#[amass::amass_telety(crate)]
pub enum IdentifierChar {
    Alphanumeric(Alphanumeric),
    Underscore(Underscore),
}

fn main() {
    let _: &[IdentifierChar] = &[
        letter::A.into(),     // IdentifierChar::Alphanumeric(Alphanumeric::Letter(Letter::A(A)))
        letter::B.into(),     // IdentifierChar::Alphanumeric(Alphanumeric::Letter(Letter::B(B)))
        letter::C.into(),     // IdentifierChar::Alphanumeric(Alphanumeric::Letter(Letter::C(C)))
        Underscore.into(),    // IdentifierChar::Underscore(Underscore)
        number::One.into(),   // IdentifierChar::Alphanumeric(Alphanumeric::Number(Number::One(One)))
        number::Two.into(),   // IdentifierChar::Alphanumeric(Alphanumeric::Number(Number::Two(Two)))
        number::Three.into(), // IdentifierChar::Alphanumeric(Alphanumeric::Number(Number::Three(Three)))
    ];
}

amass 由 telety 驱动，它在其支持的语言功能上仍有 限制。 您可以单独使用 #[amass] 和 #[telety(...)] 属性，或者简单地使用组合的 #[amass_telety(...)] 属性。

#[amass_telety(crate)]
pub enum ConflictingVariants {
    Default(i32),
    #[amass_action(ignore)]
    Alternate(i32),
}

#[amass_telety(crate, default = ignore)]
pub enum ConflictingVariants {
    #[amass_action(shallow)]
    Default(i32),
    Alternate(i32),
}

# use amass::amass_telety;

pub struct DiamondTop;

#[amass_telety(crate)]
pub struct DiamondLeft {
    Top(DiamondTop)
}

#[amass_telety(crate)]
pub struct DiamondRight {
    Top(DiamondTop)
}

#[amass_telety(crate)]
pub struct DiamondBottom {
    Left(DiamondLeft),
    Right(DiamondRight),
}
# fn main() { }