ambassador 0.5.1

Trait implementation delegation via procedural macros
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61

extern crate ambassador;

use ambassador::{delegatable_trait, delegate_to_methods};
use std::ops::DerefMut;

#[delegatable_trait]
trait MyTrait {
    fn get(&self) -> u32;
    fn into_u32(self) -> u32;
}

impl MyTrait for u32 {
    fn get(&self) -> u32 {
        *self
    }

    fn into_u32(self) -> u32 {
        self
    }
}

struct Wrap<X>(X);

#[delegate_to_methods]
#[delegate(MyTrait, target_owned = "inner", target_ref = "inner_ref")]
//~^ Error target methods have different return types
#[delegate(MyTrait, target_owned = "inner_ref", target_ref = "inner_ref")]
//~^ Error method needs to have a receiver of type "self"
#[delegate(MyTrait, target_owned = "inner", target_ref = "fail1")]
//~^ Error Note: method used in #[delegate] attribute
#[delegate(MyTrait)] //~ Error no targets were specified
impl<X> Wrap<X>
where
    X: DerefMut + Into<u32>,
    X::Target: Sized,
{
    fn inner(self) -> u32 {
        //~^ Error Note: other return type defined here
        self.0.into()
    }

    fn inner_ref(&self) -> &X::Target {
        //~^ Error Note: first return type defined here
        self.0.deref()
    }

    fn inner_mut(&mut self) -> &mut X::Target {
        self.0.deref_mut()
    }

    fn fail1() -> u32 {
        //~^ method must have a receiver
        5
    }

    fn fail2() -> u32 {
        5
    }
}

fn main() {}