#![feature(plugin)] #![plugin(mutagen_plugin)] #![feature(custom_attribute)] extern crate mutagen; #[mutate] fn something() -> bool { let n = "test".as_bytes(); *n == *b"test" } #[mutate] fn owned_eq() -> Option { let x = "Hello".to_string(); if x == "Hello" { Some(x) } else { None } } fn main() { something(); }