Refactor element-wise comparison implementation for matrices

src/matrix/mat.rs

@@ -184,27 +184,37 @@ impl<'a, T> MatrixRow<'a, T> {
     }
 }
 
-macro_rules! impl_cmp {
-    ($name:ident, $op:tt) => {
-        pub fn $name(&self, rhs: &Matrix<T>) -> BoolMatrix {
-            assert_eq!(self.rows, rhs.rows,  "…");
-            assert_eq!(self.cols, rhs.cols,  "…");
-
-            let data = self.data.iter()
-                .zip(rhs.data.iter())
+/// Implements element‐wise eq, lt, le, gt and ge for `Matrix<T>`.
+macro_rules! impl_elementwise_cmp {
+    (
+        $( $method:ident => $op:tt ),* $(,)?
+    ) => {
+        impl<T: PartialOrd> Matrix<T> {
+            $(
+            #[doc = concat!("Element‐wise comparison `x ", stringify!($op), " y`.")]
+            pub fn $method(&self, rhs: &Matrix<T>) -> BoolMatrix {
+                assert_eq!(self.rows, rhs.rows, "row count mismatch");
+                assert_eq!(self.cols, rhs.cols, "col count mismatch");
+                let data = self
+                    .data
+                    .iter()
+                    .zip(&rhs.data)
                     .map(|(a, b)| a $op b)
                     .collect();
-
                 BoolMatrix::from_vec(data, self.rows, self.cols)
             }
+            )*
+        }
     };
 }
 
-impl<T: PartialOrd> Matrix<T> {
-    impl_cmp!(lt_elementwise, <);
-    impl_cmp!(le_elementwise, <=);
-    impl_cmp!(gt_elementwise, >);
-    impl_cmp!(ge_elementwise, >=);
+// Invoke it for all five operations:
+impl_elementwise_cmp! {
+    eq_elementwise => ==,
+    lt_elementwise => <,
+    le_elementwise => <=,
+    gt_elementwise => >,
+    ge_elementwise => >=,
 }
 
 /// Generates element-wise arithmetic implementations for matrices.