compiler/rustc_error_codes/src/error_codes/E0698.md

#### Note: this error code is no longer emitted by the compiler.

When using coroutines (or async) all type variables must be bound so a
coroutine can be constructed.

Erroneous code example:

```edition2018,compile_fail,E0282
async fn bar<T>() -> () {}

async fn foo() {
    bar().await; // error: cannot infer type for `T`
}
```

In the above example `T` is unknowable by the compiler.
To fix this you must bind `T` to a concrete type such as `String`
so that a coroutine can then be constructed:

```edition2018
async fn bar<T>() -> () {}

async fn foo() {
    bar::<String>().await;
    //   ^^^^^^^^ specify type explicitly
}
```