Macro amplify::s

macro_rules! s {
    ( $str:literal ) => { ... };
}

Macro for quick & simple &str -> String conversion:

#[macro_use]
extern crate amplify;

enum Error {
    Io(String),
}

impl From<std::io::Error> for Error {
    fn from(err: std::io::Error) -> Error {
        Self::Io(s!("I/O error"))
    }
}