extern crate num;

use self::num::FromPrimitive;
use self::num::One;
use self::num::traits::PrimInt;

struct TestStruct<T> {
  val: T
}

impl<T: PrimInt> TestStruct<T> {
  pub fn new(val: T) -> TestStruct<T> { TestStruct { val: val} }

  // This fails.  Error is:
  //   error: the trait `num::traits::FromPrimitive` is not implemented for the type `T`
  pub fn add_one(&self) -> T { self.val + FromPrimitive::from_i8(1).unwrap() }

  // This does work:
  // pub fn add_one(&self) -> T { self.val + One::one() }
}

mod test {
  use super::TestStruct;

  #[test]
  fn test_foo() {
    let test_struct = TestStruct::new(1);
    assert_eq!(2, test_struct.add_one());
  }
}