// run-pass trait Stringify { fn to_string(&self) -> String; } impl Stringify for u32 { fn to_string(&self) -> String { format!("u32: {}", *self) } } impl Stringify for f32 { fn to_string(&self) -> String { format!("f32: {}", *self) } } fn print(x: T) -> String { x.to_string() } fn main() { assert_eq!(&print(5), "u32: 5"); assert_eq!(&print(5.0), "f32: 5"); }