Crates.io | inherent |
lib.rs | inherent |
version | 1.0.11 |
source | src |
created_at | 2019-07-14 18:30:27.901953 |
updated_at | 2024-01-02 06:50:01.335719 |
description | Make trait methods callable without the trait in scope |
homepage | |
repository | https://github.com/dtolnay/inherent |
max_upload_size | |
id | 149009 |
size | 30,186 |
This crate provides an attribute macro to make trait methods callable without the trait in scope.
[dependencies]
inherent = "1.0"
mod types {
use inherent::inherent;
trait Trait {
fn f(self);
}
pub struct Struct;
#[inherent]
impl Trait for Struct {
pub fn f(self) {}
}
}
fn main() {
// types::Trait is not in scope, but method can be called.
types::Struct.f();
}
Without the inherent
macro on the trait impl, this would have failed with the
following error:
error[E0599]: no method named `f` found for type `types::Struct` in the current scope
--> src/main.rs:18:19
|
8 | pub struct Struct;
| ------------------ method `f` not found for this
...
18 | types::Struct.f();
| ^
|
= help: items from traits can only be used if the trait is implemented and in scope
= note: the following trait defines an item `f`, perhaps you need to implement it:
candidate #1: `types::Trait`
The inherent
macro expands to inherent methods on the Self
type of the trait
impl that forward to the trait methods. In the case above, the generated code
would be:
impl Struct {
pub fn f(self) {
<Self as Trait>::f(self)
}
}