# Error code E0777

A literal value was used inside `#[derive]`.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    #[derive("Clone")] // error!
    struct Foo;
    }

Only paths to traits are allowed as argument inside `#[derive]`. You can find more information about the `#[derive]` attribute in the Rust Book.

    #![allow(unused)]
    fn main() {
    #[derive(Clone)] // ok!
    struct Foo;
    }