Provides a macro to simplify operator overloading.
See the documentation for details.
```rust extern crate overload; use overload::overload; use std::ops; // <- don't forget this or you'll get nasty errors
struct Val { v: i32 }
overload!((a: ?Val) + (b: ?Val) -> Val { Val { v: a.v + b.v } }); ```
The macro call in the snippet above generates the following code:
rust
impl ops::Add<Val> for Val {
type Output = Val;
fn add(self, b: Val) -> Self::Output {
let a = self;
Val { v: a.v + b.v }
}
}
impl ops::Add<&Val> for Val {
type Output = Val;
fn add(self, b: &Val) -> Self::Output {
let a = self;
Val { v: a.v + b.v }
}
}
impl ops::Add<Val> for &Val {
type Output = Val;
fn add(self, b: Val) -> Self::Output {
let a = self;
Val { v: a.v + b.v }
}
}
impl ops::Add<&Val> for &Val {
type Output = Val;
fn add(self, b: &Val) -> Self::Output {
let a = self;
Val { v: a.v + b.v }
}
}
We are now able to add Vals and &Vals in any combination:
rust
assert_eq!(Val{v:3} + Val{v:5}, Val{v:8});
assert_eq!(Val{v:3} + &Val{v:5}, Val{v:8});
assert_eq!(&Val{v:3} + Val{v:5}, Val{v:8});
assert_eq!(&Val{v:3} + &Val{v:5}, Val{v:8});