1 #![deny(trivial_numeric_casts)] 2 3 #[macro_use] 4 extern crate num_derive; 5 6 #[derive(FromPrimitive, ToPrimitive)] 7 pub enum SomeEnum { 8 A = 1, 9 } 10 11 #[test] test_trivial_numeric_casts()12fn test_trivial_numeric_casts() { 13 use num::{FromPrimitive, ToPrimitive}; 14 assert!(SomeEnum::from_u64(1).is_some()); 15 assert!(SomeEnum::from_i64(-1).is_none()); 16 assert_eq!(SomeEnum::A.to_u64(), Some(1)); 17 } 18