address comments by erickt

src/de/impls.rs

@@ -93,10 +93,6 @@ macro_rules! impl_deserialize_num_method {
     }
 }
 
-pub struct NumericVisitor<T> {
-    marker: PhantomData<T>,
-}
-
 pub struct PrimitiveVisitor<T> {
     marker: PhantomData<T>,
 }
@@ -110,18 +106,9 @@ impl<T> PrimitiveVisitor<T> {
     }
 }
 
-impl<T> NumericVisitor<T> {
-    #[inline]
-    pub fn new() -> Self {
-        NumericVisitor {
-            marker: PhantomData,
-        }
-    }
-}
-
 impl<
     T: Deserialize + FromPrimitive + str::FromStr
-> Visitor for NumericVisitor<T> {
+> Visitor for PrimitiveVisitor<T> {
     type Value = T;
 
     impl_deserialize_num_method!(isize, visit_isize, from_isize);
@@ -145,25 +132,6 @@ impl<
     }
 }
 
-impl<
-    T: Deserialize + FromPrimitive
-> Visitor for PrimitiveVisitor<T> {
-    type Value = T;
-
-    impl_deserialize_num_method!(isize, visit_isize, from_isize);
-    impl_deserialize_num_method!(i8, visit_i8, from_i8);
-    impl_deserialize_num_method!(i16, visit_i16, from_i16);
-    impl_deserialize_num_method!(i32, visit_i32, from_i32);
-    impl_deserialize_num_method!(i64, visit_i64, from_i64);
-    impl_deserialize_num_method!(usize, visit_usize, from_usize);
-    impl_deserialize_num_method!(u8, visit_u8, from_u8);
-    impl_deserialize_num_method!(u16, visit_u16, from_u16);
-    impl_deserialize_num_method!(u32, visit_u32, from_u32);
-    impl_deserialize_num_method!(u64, visit_u64, from_u64);
-    impl_deserialize_num_method!(f32, visit_f32, from_f32);
-    impl_deserialize_num_method!(f64, visit_f64, from_f64);
-}
-
 macro_rules! impl_deserialize_num {
     ($ty:ty) => {
         impl Deserialize for $ty {
@@ -171,7 +139,7 @@ macro_rules! impl_deserialize_num {
             fn deserialize<D>(deserializer: &mut D) -> Result<$ty, D::Error>
                 where D: Deserializer,
             {
-                deserializer.visit(NumericVisitor::new())
+                deserializer.visit(PrimitiveVisitor::new())
             }
         }
     }