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An attempted implementation of a trait method has the wrong number of type or
const parameters.
Erroneous code example:
```compile_fail,E0049
trait Foo {
fn foo<T: Default>(x: T) -> Self;
}
struct Bar;
// error: method `foo` has 0 type parameters but its trait declaration has 1
// type parameter
impl Foo for Bar {
fn foo(x: bool) -> Self { Bar }
}
```
For example, the `Foo` trait has a method `foo` with a type parameter `T`,
but the implementation of `foo` for the type `Bar` is missing this parameter.
To fix this error, they must have the same type parameters:
```
trait Foo {
fn foo<T: Default>(x: T) -> Self;
}
struct Bar;
impl Foo for Bar {
fn foo<T: Default>(x: T) -> Self { // ok!
Bar
}
}
```
|
