Derive IntoStaticStr

Implements From<YourEnum> and From<&'a YourEnum> for &'static str. This is useful for turning an enum variant into a static string. The Rust std provides a blanket impl of the reverse direction - i.e. impl Into<&'static str> for YourEnum.

extern crate strum;
#[macro_use] extern crate strum_macros;

#[derive(IntoStaticStr)]
enum State<'a> {
    Initial(&'a str),
    Finished
}

fn print_state<'a>(s:&'a str) {
    let state = State::Initial(s);
    // The following won't work because the lifetime is incorrect so we can use.as_static() instead.
    // let wrong: &'static str = state.as_ref();
    let right: &'static str = state.into();
    println!("{}", right);
}

fn main() {
    print_state(&"hello world".to_string())
}