penum 0.1.30

Make enum conform to a given pattern
Documentation 
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#![allow(dead_code)]
#![allow(unused)]
use penum::penum;

#[penum]
trait Trait {
    fn go(&self) -> String;
}

#[penum]
trait Trait2 {
    fn go2(&self) -> String;
}

impl Trait for i32 {
    fn go(&self) -> String {
        "todo!()".to_string()
    }
}

impl Trait for usize {
    fn go(&self) -> String {
        "todo!()".to_string()
    }
}

impl Trait2 for i32 {
    fn go2(&self) -> String {
        "todo!()".to_string()
    }
}
impl Trait2 for usize {
    fn go2(&self) -> String {
        "todo!()".to_string()
    }
}

#[penum( impl Trait for {usize, i32} )]
enum Mine {
    V1(i32),
    V2(i32),
    V3(usize, i32),
}

#[penum( (T) | (U, T) where usize: ^Trait, i32: ^Trait2 )]
enum Mine2 {
    V1(i32),
    V2(i32),
    V3(usize, i32),
}

#[penum( (T) | (U, T) where usize: ^Trait, usize: ^Trait2 )]
enum Mine3 {
    V1(i32),
    V2(i32),
    V3(usize, i32),
}

// FIXME: This skips the T dispatch.
#[penum( (T) | (U, T) where T: ^Trait, T: ^Trait2, usize: ^Trait2 )]
enum Mine4 {
    V1(i32),
    V2(i32),
    V3(usize, i32),
}

#[penum]
trait Cool {
    type Target;
    fn mine(&self, value: Self::Target) -> &i32;
}

impl Cool for i32 {
    type Target = String;
    fn mine(&self, value: String) -> &i32 {
        self
    }
}

#[penum( _ where i32: ^Cool )]
enum Mine5 {
    V1(i32),
    V2(i32),
    V3(i32, i32),
}

fn main() {
    let m = Mine::V2(20);
    let n = m.go();

    let m = Mine2::V2(20);
    let n = m.go();

    let m = Mine3::V2(20);
    let n = m.go2();
}