#![deny(trivial_numeric_casts)] #[macro_use] extern crate num_derive; #[derive(FromPrimitive, ToPrimitive)] pub enum SomeEnum { A = 1, } #[test] fn test_trivial_numeric_casts() { use num::{FromPrimitive, ToPrimitive}; assert!(SomeEnum::from_u64(1).is_some()); assert!(SomeEnum::from_i64(-1).is_none()); assert_eq!(SomeEnum::A.to_u64(), Some(1)); }