postfix and infix increment operators

README.md

@@ -508,6 +508,26 @@ auto operator~(const vec<T, Size>& xs);
 template < typename T, size_t Size >
 auto operator!(const vec<T, Size>& xs);
 
+// ++operator
+
+template < typename T, size_t Size >
+vec<T, Size>& operator++(vec<T, Size>& xs);
+
+// --operator
+
+template < typename T, size_t Size >
+vec<T, Size>& operator--(vec<T, Size>& xs);
+
+// operator++
+
+template < typename T, size_t Size >
+vec<T, Size> operator++(vec<T, Size>& xs, int);
+
+// operator--
+
+template < typename T, size_t Size >
+vec<T, Size> operator--(vec<T, Size>& xs, int);
+
 // operator+
 
 template < typename T, typename U, size_t Size >
@@ -702,6 +722,26 @@ auto operator~(const mat<T, Size>& xs);
 template < typename T, size_t Size >
 auto operator!(const mat<T, Size>& xs);
 
+// ++operator
+
+template < typename T, size_t Size >
+mat<T, Size>& operator++(mat<T, Size>& xs);
+
+// --operator
+
+template < typename T, size_t Size >
+mat<T, Size>& operator--(mat<T, Size>& xs);
+
+// operator++
+
+template < typename T, size_t Size >
+mat<T, Size> operator++(mat<T, Size>& xs, int);
+
+// operator--
+
+template < typename T, size_t Size >
+mat<T, Size> operator--(mat<T, Size>& xs, int);
+
 // operator+
 
 template < typename T, typename U, size_t Size >

headers/vmath.hpp/vmath_mat_fun.hpp

@@ -187,6 +187,38 @@ namespace vmath_hpp
         return map_join([](const vec<T, Size>& x){ return !x; }, xs);
     }
 
+    // ++operator
+
+    template < typename T, std::size_t Size >
+    constexpr mat<T, Size>& operator++(mat<T, Size>& xs) {
+        return (xs = xs + T{1});
+    }
+
+    // --operator
+
+    template < typename T, std::size_t Size >
+    constexpr mat<T, Size>& operator--(mat<T, Size>& xs) {
+        return (xs = xs - T{1});
+    }
+
+    // operator++
+
+    template < typename T, std::size_t Size >
+    constexpr mat<T, Size> operator++(mat<T, Size>& xs, int) {
+        mat<T, Size> ys = xs;
+        ++xs;
+        return ys;
+    }
+
+    // operator--
+
+    template < typename T, std::size_t Size >
+    constexpr mat<T, Size> operator--(mat<T, Size>& xs, int) {
+        mat<T, Size> ys = xs;
+        --xs;
+        return ys;
+    }
+
     // operator+
 
     template < typename T, typename U, std::size_t Size >

headers/vmath.hpp/vmath_vec_fun.hpp

@@ -238,6 +238,38 @@ namespace vmath_hpp
         return map_join([](T x){ return !x; }, xs);
     }
 
+    // ++operator
+
+    template < typename T, std::size_t Size >
+    constexpr vec<T, Size>& operator++(vec<T, Size>& xs) {
+        return (xs = xs + T{1});
+    }
+
+    // --operator
+
+    template < typename T, std::size_t Size >
+    constexpr vec<T, Size>& operator--(vec<T, Size>& xs) {
+        return (xs = xs - T{1});
+    }
+
+    // operator++
+
+    template < typename T, std::size_t Size >
+    constexpr vec<T, Size> operator++(vec<T, Size>& xs, int) {
+        vec<T, Size> ys = xs;
+        ++xs;
+        return ys;
+    }
+
+    // operator--
+
+    template < typename T, std::size_t Size >
+    constexpr vec<T, Size> operator--(vec<T, Size>& xs, int) {
+        vec<T, Size> ys = xs;
+        --xs;
+        return ys;
+    }
+
     // operator+
 
     template < typename T, typename U, std::size_t Size >

untests/vmath_mat_fun_tests.cpp

@@ -72,6 +72,20 @@ TEST_CASE("vmath/mat_fun") {
         STATIC_CHECK((int2x2(0,1,0,1) && int2x2(1,0,1,0)) == bool2x2(0,0,0,0));
         STATIC_CHECK((int2x2(0,1,0,1) || int2x2(1,0,1,0)) == bool2x2(1,1,1,1));
 
+        {
+            int2x2 v{1,2,3,4};
+            CHECK(&v == &(++v));
+            CHECK(v == int2x2{2,3,4,5});
+            CHECK(&v == &(--v));
+            CHECK(v == int2x2{1,2,3,4});
+        }
+        {
+            int2x2 v{1,2,3,4};
+            CHECK(v++ == int2x2{1,2,3,4});
+            CHECK(v == int2x2{2,3,4,5});
+            CHECK(v-- == int2x2{2,3,4,5});
+            CHECK(v == int2x2{1,2,3,4});
+        }
         {
             int2x2 v{1,2,3,4};
             CHECK(&v == &(v += 3));

untests/vmath_vec_fun_tests.cpp

@@ -49,6 +49,20 @@ TEST_CASE("vmath/vec_fun") {
         STATIC_CHECK((int2(0,1) && int2(1,0)) == bool2(0,0));
         STATIC_CHECK((int2(0,1) || int2(1,0)) == bool2(1,1));
 
+        {
+            int2 v{1,2};
+            CHECK(&v == &(++v));
+            CHECK(v == int2{2,3});
+            CHECK(&v == &(--v));
+            CHECK(v == int2{1,2});
+        }
+        {
+            int2 v{1,2};
+            CHECK(v++ == int2{1,2});
+            CHECK(v == int2{2,3});
+            CHECK(v-- == int2{2,3});
+            CHECK(v == int2{1,2});
+        }
         {
             int2 v{1,2};
             CHECK(&v == &(v += 3));