diff --git a/headers/vmath.hpp/vmath_mat_fun.hpp b/headers/vmath.hpp/vmath_mat_fun.hpp
index 3764677..b3a4835 100644
--- a/headers/vmath.hpp/vmath_mat_fun.hpp
+++ b/headers/vmath.hpp/vmath_mat_fun.hpp
@@ -18,55 +18,28 @@ namespace vmath_hpp::detail::impl
 {
     template < typename A, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    mat<typename std::invoke_result_t<
-        F,
-        vec<A, Size>
-    >::component_type, Size>
-    map_join_impl(
+    auto map_join_impl(
         F&& f,
         const mat<A, Size>& a,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is])... };
+        return mat{ f(a[Is])... };
     }
 
     template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    mat<typename std::invoke_result_t<
-        F,
-        vec<A, Size>,
-        vec<B, Size>
-    >::component_type, Size>
-    map_join_impl(
+    auto map_join_impl(
         F&& f,
         const mat<A, Size>& a,
         const mat<B, Size>& b,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is], b[Is])... };
-    }
-
-    template < typename A, typename B, typename C, std::size_t Size, typename F, std::size_t... Is >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    mat<typename std::invoke_result_t<
-        F,
-        vec<A, Size>,
-        vec<B, Size>,
-        vec<C, Size>
-    >::component_type, Size>
-    map_join_impl(
-        F&& f,
-        const mat<A, Size>& a,
-        const mat<B, Size>& b,
-        const mat<C, Size>& c,
-        std::index_sequence<Is...>)
-    {
-        return { f(a[Is], b[Is], c[Is])... };
+        return mat{ f(a[Is], b[Is])... };
     }
 
     template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold_join_impl(
+    auto fold_join_impl(
         F&& f,
         A init,
         const mat<B, Size>& b,
@@ -75,39 +48,57 @@ namespace vmath_hpp::detail::impl
         return ((init = f(std::move(init), b[Is])), ...);
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F, std::size_t... Is >
+    template < typename A, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold_join_impl(
-        F&& f,
-        A init,
-        const vec<B, Size>& b,
-        const mat<C, Size>& c,
-        std::index_sequence<Is...>)
-    {
-        return ((init = f(std::move(init), b[Is], c[Is])), ...);
-    }
-
-    template < typename A, typename B, typename C, std::size_t Size, typename F, std::size_t... Is >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold_join_impl(
-        F&& f,
-        A init,
-        const mat<B, Size>& b,
-        const mat<C, Size>& c,
-        std::index_sequence<Is...>)
-    {
-        return ((init = f(std::move(init), b[Is], c[Is])), ...);
-    }
-
-    template < typename A, std::size_t Size, typename F, std::size_t I, std::size_t... Is >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    vec<A, Size> fold1_join_impl(
+    auto fold1_and_join_impl(
         F&& f,
         const mat<A, Size>& a,
-        std::index_sequence<I, Is...>)
+        std::index_sequence<Is...>)
     {
-        vec<A, Size> init = a[I];
-        return ((init = f(std::move(init), a[Is])), ...);
+        return (... && f(a[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_and_join_impl(
+        F&& f,
+        const mat<A, Size>& a,
+        const mat<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... && f(a[Is], b[Is]));
+    }
+
+    template < typename A, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join_impl(
+        F&& f,
+        const mat<A, Size>& a,
+        std::index_sequence<Is...>)
+    {
+        return (... || f(a[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join_impl(
+        F&& f,
+        const mat<A, Size>& a,
+        const mat<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... || f(a[Is], b[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_plus_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        const mat<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... + f(a[Is], b[Is]));
     }
 }
 
@@ -125,34 +116,40 @@ namespace vmath_hpp::detail
         return impl::map_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto map_join(F&& f, const mat<A, Size>& a, const mat<B, Size>& b, const mat<C, Size>& c) {
-        return impl::map_join_impl(std::forward<F>(f), a, b, c, std::make_index_sequence<Size>{});
-    }
-
     template < typename A, typename B, std::size_t Size, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
     auto fold_join(F&& f, A init, const mat<B, Size>& b) {
         return impl::fold_join_impl(std::forward<F>(f), std::move(init), b, std::make_index_sequence<Size>{});
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F >
+    template < typename A, std::size_t Size, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold_join(F&& f, A init, const vec<B, Size>& b, const mat<C, Size>& c) {
-        return impl::fold_join_impl(std::forward<F>(f), std::move(init), b, c, std::make_index_sequence<Size>{});
+    auto fold1_and_join(F&& f, const mat<A, Size>& a) {
+        return impl::fold1_and_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F >
+    template < typename A, typename B, std::size_t Size, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold_join(F&& f, A init, const mat<B, Size>& b, const mat<C, Size>& c) {
-        return impl::fold_join_impl(std::forward<F>(f), std::move(init), b, c, std::make_index_sequence<Size>{});
+    auto fold1_and_join(F&& f, const mat<A, Size>& a, const mat<B, Size>& b) {
+        return impl::fold1_and_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
     }
 
     template < typename A, std::size_t Size, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold1_join(F&& f, const mat<A, Size>& a) {
-        return impl::fold1_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
+    auto fold1_or_join(F&& f, const mat<A, Size>& a) {
+        return impl::fold1_or_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join(F&& f, const mat<A, Size>& a, const mat<B, Size>& b) {
+        return impl::fold1_or_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_plus_join(F&& f, const vec<A, Size>& a, const mat<B, Size>& b) {
+        return impl::fold1_plus_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
     }
 }
 
@@ -262,17 +259,12 @@ namespace vmath_hpp
 
     template < typename T, typename U, std::size_t Size >
     [[nodiscard]] constexpr auto operator*(const vec<T, Size>& xs, const mat<U, Size>& ys) {
-        using V = decltype(std::declval<T>() * std::declval<U>());
-        return fold_join([](const vec<V, Size>& acc, T x, const vec<U, Size>& y){
-            return acc + x * y;
-        }, vec<V, Size>{}, xs, ys);
+        return fold1_plus_join([](T x, const vec<U, Size>& y){ return x * y; }, xs, ys);
     }
 
     template < typename T, typename U, std::size_t Size >
     [[nodiscard]] constexpr auto operator*(const mat<T, Size>& xs, const mat<U, Size>& ys) {
-        return map_join([&ys](const vec<T, Size>& x){
-            return x * ys;
-        }, xs);
+        return map_join([&ys](const vec<T, Size>& x){ return x * ys; }, xs);
     }
 
     // operator*=
@@ -436,18 +428,14 @@ namespace vmath_hpp
 
     template < typename T, std::size_t Size >
     [[nodiscard]] constexpr bool operator==(const mat<T, Size>& xs, const mat<T, Size>& ys) {
-        return fold_join([](bool acc, const vec<T, Size>& x, const vec<T, Size>& y){
-            return acc && (x == y);
-        }, true, xs, ys);
+        return fold1_and_join([](const vec<T, Size>& x, const vec<T, Size>& y){ return x == y; }, xs, ys);
     }
 
     // operator!=
 
     template < typename T, std::size_t Size >
     [[nodiscard]] constexpr bool operator!=(const mat<T, Size>& xs, const mat<T, Size>& ys) {
-        return fold_join([](bool acc, const vec<T, Size>& x, const vec<T, Size>& y){
-            return acc || (x != y);
-        }, false, xs, ys);
+        return fold1_or_join([](const vec<T, Size>& x, const vec<T, Size>& y){ return x != y; }, xs, ys);
     }
 
     // operator<
@@ -475,13 +463,13 @@ namespace vmath_hpp
     template < typename T, std::size_t Size
              , typename U = decltype(any(std::declval<vec<T, Size>>())) >
     [[nodiscard]] constexpr U any(const mat<T, Size>& xs) {
-        return fold_join([](U acc, const vec<T, Size>& x){ return acc || any(x); }, U{false}, xs);
+        return fold1_or_join([](const vec<T, Size>& x){ return any(x); }, xs);
     }
 
     template < typename T, std::size_t Size
              , typename U = decltype(all(std::declval<vec<T, Size>>())) >
     [[nodiscard]] constexpr U all(const mat<T, Size>& xs) {
-        return fold_join([](U acc, const vec<T, Size>& x){ return acc && all(x); }, U{true}, xs);
+        return fold1_and_join([](const vec<T, Size>& x){ return all(x); }, xs);
     }
 
     template < typename T, std::size_t Size
diff --git a/headers/vmath.hpp/vmath_qua_fun.hpp b/headers/vmath.hpp/vmath_qua_fun.hpp
index 1296647..fc4f0e1 100644
--- a/headers/vmath.hpp/vmath_qua_fun.hpp
+++ b/headers/vmath.hpp/vmath_qua_fun.hpp
@@ -22,41 +22,11 @@ namespace vmath_hpp::detail
         return qua(map_join(std::forward<F>(f), vec{a}));
     }
 
-    template < typename A, typename B, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto map_join(F&& f, const qua<A>& a, const qua<B>& b) {
-        return qua(map_join(std::forward<F>(f), vec{a}, vec{b}));
-    }
-
-    template < typename A, typename B, typename C, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto map_join(F&& f, const qua<A>& a, const qua<B>& b, const qua<C>& c) {
-        return qua(map_join(std::forward<F>(f), vec{a}, vec{b}, vec{c}));
-    }
-
-    template < typename A, typename B, typename C, typename D, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto map_join(F&& f, const qua<A>& a, const qua<B>& b, const qua<C>& c, const qua<D>& d) {
-        return qua(map_join(std::forward<F>(f), vec{a}, vec{b}, vec{c}, vec{d}));
-    }
-
     template < typename A, typename B, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
     auto fold_join(F&& f, A init, const qua<B>& b) {
         return fold_join(std::forward<F>(f), std::move(init), vec{b});
     }
-
-    template < typename A, typename B, typename C, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold_join(F&& f, A init, const qua<B>& b, const qua<C>& c) {
-        return fold_join(std::forward<F>(f), std::move(init), vec{b}, vec{c});
-    }
-
-    template < typename A, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold1_join(F&& f, const qua<A>& a) {
-        return fold1_join(std::forward<F>(f), vec{a});
-    }
 }
 
 //
diff --git a/headers/vmath.hpp/vmath_vec_fun.hpp b/headers/vmath.hpp/vmath_vec_fun.hpp
index c2b057f..115adec 100644
--- a/headers/vmath.hpp/vmath_vec_fun.hpp
+++ b/headers/vmath.hpp/vmath_vec_fun.hpp
@@ -15,40 +15,40 @@ namespace vmath_hpp::detail::impl
 {
     template < typename A, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    vec<std::invoke_result_t<F, A>, Size> map_join_impl(
+    auto map_join_impl(
         F&& f,
         const vec<A, Size>& a,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is])... };
+        return vec{ f(a[Is])... };
     }
 
     template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    vec<std::invoke_result_t<F, A, B>, Size> map_join_impl(
+    auto map_join_impl(
         F&& f,
         const vec<A, Size>& a,
         const vec<B, Size>& b,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is], b[Is])... };
+        return vec{ f(a[Is], b[Is])... };
     }
 
     template < typename A, typename B, typename C, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    vec<std::invoke_result_t<F, A, B, C>, Size> map_join_impl(
+    auto map_join_impl(
         F&& f,
         const vec<A, Size>& a,
         const vec<B, Size>& b,
         const vec<C, Size>& c,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is], b[Is], c[Is])... };
+        return vec{ f(a[Is], b[Is], c[Is])... };
     }
 
     template < typename A, typename B, typename C, typename D, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    vec<std::invoke_result_t<F, A, B, C, D>, Size> map_join_impl(
+    auto map_join_impl(
         F&& f,
         const vec<A, Size>& a,
         const vec<B, Size>& b,
@@ -56,12 +56,12 @@ namespace vmath_hpp::detail::impl
         const vec<D, Size>& d,
         std::index_sequence<Is...>)
     {
-        return { f(a[Is], b[Is], c[Is], d[Is])... };
+        return vec{ f(a[Is], b[Is], c[Is], d[Is])... };
     }
 
     template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold_join_impl(
+    auto fold_join_impl(
         F&& f,
         A init,
         const vec<B, Size>& b,
@@ -70,21 +70,9 @@ namespace vmath_hpp::detail::impl
         return ((init = f(std::move(init), b[Is])), ...);
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F, std::size_t... Is >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold_join_impl(
-        F&& f,
-        A init,
-        const vec<B, Size>& b,
-        const vec<C, Size>& c,
-        std::index_sequence<Is...>)
-    {
-        return ((init = f(std::move(init), b[Is], c[Is])), ...);
-    }
-
     template < typename A, std::size_t Size, typename F, std::size_t I, std::size_t... Is >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    A fold1_join_impl(
+    auto fold1_join_impl(
         F&& f,
         const vec<A, Size>& a,
         std::index_sequence<I, Is...>)
@@ -92,6 +80,59 @@ namespace vmath_hpp::detail::impl
         A init = a[I];
         return ((init = f(std::move(init), a[Is])), ...);
     }
+
+    template < typename A, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_and_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        std::index_sequence<Is...>)
+    {
+        return (... && f(a[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_and_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        const vec<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... && f(a[Is], b[Is]));
+    }
+
+    template < typename A, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        std::index_sequence<Is...>)
+    {
+        return (... || f(a[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        const vec<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... || f(a[Is], b[Is]));
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F, std::size_t... Is >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_plus_join_impl(
+        F&& f,
+        const vec<A, Size>& a,
+        const vec<B, Size>& b,
+        std::index_sequence<Is...>)
+    {
+        return (... + f(a[Is], b[Is]));
+    }
 }
 
 namespace vmath_hpp::detail
@@ -126,17 +167,41 @@ namespace vmath_hpp::detail
         return impl::fold_join_impl(std::forward<F>(f), std::move(init), b, std::make_index_sequence<Size>{});
     }
 
-    template < typename A, typename B, typename C, std::size_t Size, typename F >
-    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
-    auto fold_join(F&& f, A init, const vec<B, Size>& b, const vec<C, Size>& c) {
-        return impl::fold_join_impl(std::forward<F>(f), std::move(init), b, c, std::make_index_sequence<Size>{});
-    }
-
     template < typename A, std::size_t Size, typename F >
     [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
     auto fold1_join(F&& f, const vec<A, Size>& a) {
         return impl::fold1_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
     }
+
+    template < typename A, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_and_join(F&& f, const vec<A, Size>& a) {
+        return impl::fold1_and_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_and_join(F&& f, const vec<A, Size>& a, const vec<B, Size>& b) {
+        return impl::fold1_and_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join(F&& f, const vec<A, Size>& a) {
+        return impl::fold1_or_join_impl(std::forward<F>(f), a, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_or_join(F&& f, const vec<A, Size>& a, const vec<B, Size>& b) {
+        return impl::fold1_or_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
+    }
+
+    template < typename A, typename B, std::size_t Size, typename F >
+    [[nodiscard]] constexpr VMATH_HPP_FORCE_INLINE
+    auto fold1_plus_join(F&& f, const vec<A, Size>& a, const vec<B, Size>& b) {
+        return impl::fold1_plus_join_impl(std::forward<F>(f), a, b, std::make_index_sequence<Size>{});
+    }
 }
 
 //
@@ -414,18 +479,14 @@ namespace vmath_hpp
 
     template < typename T, std::size_t Size >
     [[nodiscard]] constexpr bool operator==(const vec<T, Size>& xs, const vec<T, Size>& ys) {
-        return fold_join([](bool acc, T x, T y){
-            return acc && x == y;
-        }, true, xs, ys);
+        return fold1_and_join([](T x, T y){ return x == y; }, xs, ys);
     }
 
     // operator!=
 
     template < typename T, std::size_t Size >
     [[nodiscard]] constexpr bool operator!=(const vec<T, Size>& xs, const vec<T, Size>& ys) {
-        return fold_join([](bool acc, T x, T y){
-            return acc || x != y;
-        }, false, xs, ys);
+        return fold1_or_join([](T x, T y){ return x != y; }, xs, ys);
     }
 
     // operator<
@@ -778,9 +839,7 @@ namespace vmath_hpp
     template < typename T, typename U, std::size_t Size
              , typename V = decltype(std::declval<T>() * std::declval<U>()) >
     [[nodiscard]] constexpr V dot(const vec<T, Size>& xs, const vec<U, Size>& ys) {
-        return fold_join([](V acc, T x, U y){
-            return acc + (x * y);
-        }, V{0}, xs, ys);
+        return fold1_plus_join([](T x, U y){ return x * y; }, xs, ys);
     }
 
     template < typename T, std::size_t Size >
@@ -860,13 +919,13 @@ namespace vmath_hpp
     template < typename T, std::size_t Size
              , typename U = decltype(any(std::declval<T>())) >
     [[nodiscard]] constexpr U any(const vec<T, Size>& xs) {
-        return fold_join([](U acc, T x){ return acc || any(x); }, U{false}, xs);
+        return fold1_or_join([](T x){ return any(x); }, xs);
     }
 
     template < typename T, std::size_t Size
              , typename U = decltype(all(std::declval<T>())) >
     [[nodiscard]] constexpr U all(const vec<T, Size>& xs) {
-        return fold_join([](U acc, T x){ return acc && all(x); }, U{true}, xs);
+        return fold1_and_join([](T x){ return all(x); }, xs);
     }
 
     template < typename T, std::size_t Size
diff --git a/untests/vmath_mat_fun_tests.cpp b/untests/vmath_mat_fun_tests.cpp
index d068acc..a91252e 100644
--- a/untests/vmath_mat_fun_tests.cpp
+++ b/untests/vmath_mat_fun_tests.cpp
@@ -30,32 +30,6 @@ namespace
 }
 
 TEST_CASE("vmath/mat_fun") {
-    SUBCASE("detail") {
-        STATIC_CHECK(map_join([](const int2& x){
-            return x * 2;
-        }, int2x2{}) == int2x2(2,0,0,2));
-
-        STATIC_CHECK(map_join([](const int2& x, const int2& y){
-            return x + y;
-        }, int2x2{}, int2x2{}) == int2x2(2,0,0,2));
-
-        STATIC_CHECK(map_join([](const int2& x, const int2& y, const int2& z){
-            return x + y + z;
-        }, int2x2{}, int2x2{}, int2x2{}) == int2x2(3,0,0,3));
-
-        STATIC_CHECK(fold_join([](int acc, const int2& x){
-            return acc + x.x;
-        }, 0, int2x2{}) == 1);
-
-        STATIC_CHECK(fold_join([](int acc, const int2& x, const int2& y){
-            return acc + x.x + y.x;
-        }, 0, int2x2{}, int2x2{}) == 2);
-
-        STATIC_CHECK(fold1_join([](const int2& acc, const int2& x){
-            return acc + x;
-        }, int2x2{}) == int2(1,1));
-    }
-
     SUBCASE("operators") {
         STATIC_CHECK(+int2x2(1,-2,3,-4) == int2x2(1,-2,3,-4));
         STATIC_CHECK(-int2x2(1,-2,3,-4) == int2x2(-1,2,-3,4));
diff --git a/untests/vmath_vec_fun_tests.cpp b/untests/vmath_vec_fun_tests.cpp
index f9fc0b9..b9eb76e 100644
--- a/untests/vmath_vec_fun_tests.cpp
+++ b/untests/vmath_vec_fun_tests.cpp
@@ -13,36 +13,6 @@ namespace
 }
 
 TEST_CASE("vmath/vec_fun") {
-    SUBCASE("Detail") {
-        STATIC_CHECK(map_join([](const int& x){
-            return x * 2;
-        }, vec{1,2,3,4}) == vec{2,4,6,8});
-
-        STATIC_CHECK(map_join([](const int& x, const int& y){
-            return x + y;
-        }, vec{1,2,3,4}, vec{2,3,4,5}) == vec{3,5,7,9});
-
-        STATIC_CHECK(map_join([](const int& x, const int& y, const int& z){
-            return x + y + z;
-        }, vec{1,2,3,4}, vec{2,3,4,5}, vec{3,4,5,6}) == vec{6,9,12,15});
-
-        STATIC_CHECK(map_join([](const int& x, const int& y, const int& z, const int& w){
-            return x + y + z + w;
-        }, vec{1,2,3,4}, vec{2,3,4,5}, vec{3,4,5,6}, vec{4,5,6,7}) == vec{10,14,18,22});
-
-        STATIC_CHECK(fold_join([](int acc, const int& x){
-            return acc - x;
-        }, 0, vec{1,2,3,4}) == -10);
-
-        STATIC_CHECK(fold_join([](int acc, const int& x, const int& y){
-            return acc - x - y;
-        }, 0, vec{1,2,3,4}, vec{2,3,4,5}) == -24);
-
-        STATIC_CHECK(fold1_join([](const int& acc, const int& x){
-            return acc - x;
-        }, vec{1,2,3,4}) == -8);
-    }
-
     SUBCASE("Operators") {
         STATIC_CHECK(+int2(1,-2) == int2(1,-2));
         STATIC_CHECK(-int2(1,-2) == int2(-1,2));