diff --git a/complex/src/lib.rs b/complex/src/lib.rs
index e43525e..b0c2e4c 100644
--- a/complex/src/lib.rs
+++ b/complex/src/lib.rs
@@ -521,54 +521,54 @@ impl<T: Clone + Num> Div<Complex<T>> for Complex<T> {
 mod opassign {
     use std::ops::{AddAssign, SubAssign, MulAssign, DivAssign};
 
-    use traits::Num;
+    use traits::NumAssign;
 
     use Complex;
 
-    impl<T: Clone + Num> AddAssign for Complex<T> {
+    impl<T: Clone + NumAssign> AddAssign for Complex<T> {
         fn add_assign(&mut self, other: Complex<T>) {
             *self = self.clone() + other;
         }
     }
 
-    impl<T: Clone + Num> SubAssign for Complex<T> {
+    impl<T: Clone + NumAssign> SubAssign for Complex<T> {
         fn sub_assign(&mut self, other: Complex<T>) {
             *self = self.clone() - other;
         }
     }
 
-    impl<T: Clone + Num> MulAssign for Complex<T> {
+    impl<T: Clone + NumAssign> MulAssign for Complex<T> {
         fn mul_assign(&mut self, other: Complex<T>) {
             *self = self.clone() * other;
         }
     }
 
-    impl<T: Clone + Num> DivAssign for Complex<T> {
+    impl<T: Clone + NumAssign> DivAssign for Complex<T> {
         fn div_assign(&mut self, other: Complex<T>) {
             *self = self.clone() / other;
         }
     }
 
-    impl<T: Num + AddAssign> AddAssign<T> for Complex<T> {
+    impl<T: Clone + NumAssign> AddAssign<T> for Complex<T> {
         fn add_assign(&mut self, other: T) {
             self.re += other;
         }
     }
 
-    impl<T: Num + SubAssign> SubAssign<T> for Complex<T> {
+    impl<T: Clone + NumAssign> SubAssign<T> for Complex<T> {
         fn sub_assign(&mut self, other: T) {
             self.re -= other;
         }
     }
 
-    impl<T: Clone + Num + MulAssign> MulAssign<T> for Complex<T> {
+    impl<T: Clone + NumAssign> MulAssign<T> for Complex<T> {
         fn mul_assign(&mut self, other: T) {
             self.re *= other.clone();
             self.im *= other;
         }
     }
 
-    impl<T: Clone + Num + DivAssign> DivAssign<T> for Complex<T> {
+    impl<T: Clone + NumAssign> DivAssign<T> for Complex<T> {
         fn div_assign(&mut self, other: T) {
             self.re /= other.clone();
             self.im /= other;
@@ -577,13 +577,13 @@ mod opassign {
 
     macro_rules! forward_op_assign {
         (impl $imp:ident, $method:ident) => {
-            impl<'a, T: Clone + Num> $imp<&'a Complex<T>> for Complex<T> {
+            impl<'a, T: Clone + NumAssign> $imp<&'a Complex<T>> for Complex<T> {
                 #[inline]
                 fn $method(&mut self, other: &Complex<T>) {
                     self.$method(other.clone())
                 }
             }
-            impl<'a, T: Clone + Num + $imp> $imp<&'a T> for Complex<T> {
+            impl<'a, T: Clone + NumAssign> $imp<&'a T> for Complex<T> {
                 #[inline]
                 fn $method(&mut self, other: &T) {
                     self.$method(other.clone())