num: implement `Hash` for `Complex` and `Ratio`

src/libnum/complex.rs

@@ -12,13 +12,13 @@
 //! Complex numbers.
 
 use std::fmt;
-use std::num::{Zero,One,ToStrRadix};
+use std::num::{Zero, One, ToStrRadix};
 
 // FIXME #1284: handle complex NaN & infinity etc. This
 // probably doesn't map to C's _Complex correctly.
 
 /// A complex number in Cartesian form.
-#[deriving(PartialEq,Clone)]
+#[deriving(PartialEq, Clone, Hash)]
 pub struct Complex<T> {
     /// Real portion of the complex number
     pub re: T,
@@ -193,7 +193,8 @@ mod test {
     #![allow(non_uppercase_statics)]
 
     use super::{Complex64, Complex};
-    use std::num::{Zero,One,Float};
+    use std::num::{Zero, One, Float};
+    use std::hash::hash;
 
     pub static _0_0i : Complex64 = Complex { re: 0.0, im: 0.0 };
     pub static _1_0i : Complex64 = Complex { re: 1.0, im: 0.0 };
@@ -367,4 +368,14 @@ mod test {
         test(-_neg1_1i, "1-1i".to_string());
         test(_05_05i, "0.5+0.5i".to_string());
     }
+
+    #[test]
+    fn test_hash() {
+        let a = Complex::new(0i32, 0i32);
+        let b = Complex::new(1i32, 0i32);
+        let c = Complex::new(0i32, 1i32);
+        assert!(hash(&a) != hash(&b));
+        assert!(hash(&b) != hash(&c));
+        assert!(hash(&c) != hash(&a));
+    }
 }

src/libnum/rational.rs

@@ -21,7 +21,7 @@ use std::num::{Zero, One, ToStrRadix, FromStrRadix};
 use bigint::{BigInt, BigUint, Sign, Plus, Minus};
 
 /// Represents the ratio between 2 numbers.
-#[deriving(Clone)]
+#[deriving(Clone, Hash)]
 #[allow(missing_doc)]
 pub struct Ratio<T> {
     numer: T,
@@ -381,6 +381,7 @@ mod test {
     use super::{Ratio, Rational, BigRational};
     use std::num::{Zero, One, FromStrRadix, FromPrimitive, ToStrRadix};
     use std::from_str::FromStr;
+    use std::hash::hash;
     use std::num;
 
     pub static _0 : Rational = Ratio { numer: 0, denom: 1};
@@ -728,4 +729,10 @@ mod test {
         assert!(! _neg1_2.is_positive());
         assert!(! _1_2.is_negative());
     }
+
+    #[test]
+    fn test_hash() {
+        assert!(hash(&_0) != hash(&_1));
+        assert!(hash(&_0) != hash(&_3_2));
+    }
 }