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You need to specify a specific implementation of the trait in order to call the
method.
Erroneous code example:
```compile_fail,E0790
trait Coroutine {
fn create() -> u32;
}
struct Impl;
impl Coroutine for Impl {
fn create() -> u32 { 1 }
}
struct AnotherImpl;
impl Coroutine for AnotherImpl {
fn create() -> u32 { 2 }
}
let cont: u32 = Coroutine::create();
// error, impossible to choose one of Coroutine trait implementation
// Should it be Impl or AnotherImpl, maybe something else?
```
This error can be solved by adding type annotations that provide the missing
information to the compiler. In this case, the solution is to use a concrete
type:
```
trait Coroutine {
fn create() -> u32;
}
struct AnotherImpl;
impl Coroutine for AnotherImpl {
fn create() -> u32 { 2 }
}
let gen1 = AnotherImpl::create();
// if there are multiple methods with same name (different traits)
let gen2 = <AnotherImpl as Coroutine>::create();
```
|
