From 17fd0900a4cb545d5d9b35f90bc4393956905041 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sat, 22 Oct 2022 09:02:40 +0200
Subject: [PATCH] refactor: expression template operations now take function
 parameters

---
 .../include/units/bits/expression_template.h  | 106 +++++++++---------
 src/core/include/units/dimension.h            |  28 ++---
 2 files changed, 67 insertions(+), 67 deletions(-)

diff --git a/src/core/include/units/bits/expression_template.h b/src/core/include/units/bits/expression_template.h
index e7ead18e..07dac42c 100644
--- a/src/core/include/units/bits/expression_template.h
+++ b/src/core/include/units/bits/expression_template.h
@@ -250,17 +250,17 @@ struct expr_simplify<type_list<power<T, Ints1...>, NRest...>, type_list<power<T,
 
 
 // expr_less
-template<typename T1, typename T2, template<typename, typename> typename Pred>
-struct expr_less_impl : Pred<T1, T2> {};
+template<typename Lhs, typename Rhs, template<typename, typename> typename Pred>
+struct expr_less_impl : Pred<Lhs, Rhs> {};
 
-template<typename T1, int... Ints1, typename T2, int... Ints2, template<typename, typename> typename Pred>
-struct expr_less_impl<power<T1, Ints1...>, power<T2, Ints2...>, Pred> : Pred<T1, T2> {};
+template<typename Lhs, int... Ints1, typename Rhs, int... Ints2, template<typename, typename> typename Pred>
+struct expr_less_impl<power<Lhs, Ints1...>, power<Rhs, Ints2...>, Pred> : Pred<Lhs, Rhs> {};
 
-template<typename T1, int... Ints, typename T2, template<typename, typename> typename Pred>
-struct expr_less_impl<power<T1, Ints...>, T2, Pred> : Pred<T1, T2> {};
+template<typename Lhs, int... Ints, typename Rhs, template<typename, typename> typename Pred>
+struct expr_less_impl<power<Lhs, Ints...>, Rhs, Pred> : Pred<Lhs, Rhs> {};
 
-template<typename T1, typename T2, int... Ints, template<typename, typename> typename Pred>
-struct expr_less_impl<T1, power<T2, Ints...>, Pred> : Pred<T1, T2> {};
+template<typename Lhs, typename Rhs, int... Ints, template<typename, typename> typename Pred>
+struct expr_less_impl<Lhs, power<Rhs, Ints...>, Pred> : Pred<Lhs, Rhs> {};
 
 template<typename T, int... Ints, template<typename, typename> typename Pred>
 struct expr_less_impl<T, power<T, Ints...>, Pred> : std::true_type {};
@@ -271,8 +271,8 @@ struct expr_less_impl<T, power<T, Ints...>, Pred> : std::true_type {};
  * Algorithm accounts not only for explicit types but also for the case when they
  * are wrapped within `power<T, Num, Den>`.
  */
-template<typename T1, typename T2, template<typename, typename> typename Pred>
-using expr_less = expr_less_impl<T1, T2, Pred>;
+template<typename Lhs, typename Rhs, template<typename, typename> typename Pred>
+using expr_less = expr_less_impl<Lhs, Rhs, Pred>;
 
 
 // expr_fractions
@@ -355,34 +355,34 @@ template<typename NumList, typename DenList, typename OneType, template<typename
 /**
  * @brief Multiplies two sorted expression template specs
  *
- * @tparam T1 lhs of the operation
- * @tparam T2 rhs of the operation
+ * @tparam To destination type list to put the result to
  * @tparam OneType type that represents the value `1`
  * @tparam Pred binary less then predicate
- * @tparam To destination type list to put the result to
+ * @tparam Lhs lhs of the operation
+ * @tparam Rhs rhs of the operation
  */
-template<typename T1, typename T2, typename OneType, template<typename, typename> typename Pred,
-         template<typename...> typename To>
-[[nodiscard]] consteval auto expr_multiply()
+template<template<typename...> typename To, typename OneType, template<typename, typename> typename Pred, typename Lhs,
+         typename Rhs>
+[[nodiscard]] consteval auto expr_multiply(Lhs, Rhs)
 {
-  if constexpr (is_same_v<T1, OneType>) {
-    return T2{};
-  } else if constexpr (is_same_v<T2, OneType>) {
-    return T1{};
-  } else if constexpr (is_specialization_of<T1, To> && is_specialization_of<T2, To>) {
+  if constexpr (is_same_v<Lhs, OneType>) {
+    return Rhs{};
+  } else if constexpr (is_same_v<Rhs, OneType>) {
+    return Lhs{};
+  } else if constexpr (is_specialization_of<Lhs, To> && is_specialization_of<Rhs, To>) {
     // two derived dimensions
-    return get_optimized_expression<type_list_merge_sorted<typename T1::_num_, typename T2::_num_, Pred>,
-                                    type_list_merge_sorted<typename T1::_den_, typename T2::_den_, Pred>, OneType, Pred,
-                                    To>();
-  } else if constexpr (is_specialization_of<T1, To>) {
-    return get_optimized_expression<type_list_merge_sorted<typename T1::_num_, type_list<T2>, Pred>, typename T1::_den_,
-                                    OneType, Pred, To>();
-  } else if constexpr (is_specialization_of<T2, To>) {
-    return get_optimized_expression<type_list_merge_sorted<typename T2::_num_, type_list<T1>, Pred>, typename T2::_den_,
-                                    OneType, Pred, To>();
+    return get_optimized_expression<type_list_merge_sorted<typename Lhs::_num_, typename Rhs::_num_, Pred>,
+                                    type_list_merge_sorted<typename Lhs::_den_, typename Rhs::_den_, Pred>, OneType,
+                                    Pred, To>();
+  } else if constexpr (is_specialization_of<Lhs, To>) {
+    return get_optimized_expression<type_list_merge_sorted<typename Lhs::_num_, type_list<Rhs>, Pred>,
+                                    typename Lhs::_den_, OneType, Pred, To>();
+  } else if constexpr (is_specialization_of<Rhs, To>) {
+    return get_optimized_expression<type_list_merge_sorted<typename Rhs::_num_, type_list<Lhs>, Pred>,
+                                    typename Rhs::_den_, OneType, Pred, To>();
   } else {
     // two base dimensions
-    return get_optimized_expression<type_list_merge_sorted<type_list<T1>, type_list<T2>, Pred>, type_list<>, OneType,
+    return get_optimized_expression<type_list_merge_sorted<type_list<Lhs>, type_list<Rhs>, Pred>, type_list<>, OneType,
                                     Pred, To>();
   }
 }
@@ -390,34 +390,34 @@ template<typename T1, typename T2, typename OneType, template<typename, typename
 /**
  * @brief Divides two sorted expression template specs
  *
- * @tparam T1 lhs of the operation
- * @tparam T2 rhs of the operation
+ * @tparam To destination type list to put the result to
  * @tparam OneType type that represents the value `1`
  * @tparam Pred binary less then predicate
- * @tparam To destination type list to put the result to
+ * @tparam Lhs lhs of the operation
+ * @tparam Rhs rhs of the operation
  */
-template<typename T1, typename T2, typename OneType, template<typename, typename> typename Pred,
-         template<typename...> typename To>
-[[nodiscard]] consteval auto expr_divide()
+template<template<typename...> typename To, typename OneType, template<typename, typename> typename Pred, typename Lhs,
+         typename Rhs>
+[[nodiscard]] consteval auto expr_divide(Lhs, Rhs)
 {
-  if constexpr (is_same_v<T1, T2>) {
+  if constexpr (is_same_v<Lhs, Rhs>) {
     return OneType{};
-  } else if constexpr (is_same_v<T2, OneType>) {
-    return T1{};
-  } else if constexpr (is_specialization_of<T1, To> && is_specialization_of<T2, To>) {
+  } else if constexpr (is_same_v<Rhs, OneType>) {
+    return Lhs{};
+  } else if constexpr (is_specialization_of<Lhs, To> && is_specialization_of<Rhs, To>) {
     // two derived dimensions
-    return get_optimized_expression<type_list_merge_sorted<typename T1::_num_, typename T2::_den_, Pred>,
-                                    type_list_merge_sorted<typename T1::_den_, typename T2::_num_, Pred>, OneType, Pred,
-                                    To>();
-  } else if constexpr (is_specialization_of<T1, To>) {
-    return get_optimized_expression<typename T1::_num_, type_list_merge_sorted<typename T1::_den_, type_list<T2>, Pred>,
-                                    OneType, Pred, To>();
-  } else if constexpr (is_specialization_of<T2, To>) {
-    return get_optimized_expression<type_list_merge_sorted<typename T2::_den_, type_list<T1>, Pred>, typename T2::_num_,
-                                    OneType, Pred, To>();
+    return get_optimized_expression<type_list_merge_sorted<typename Lhs::_num_, typename Rhs::_den_, Pred>,
+                                    type_list_merge_sorted<typename Lhs::_den_, typename Rhs::_num_, Pred>, OneType,
+                                    Pred, To>();
+  } else if constexpr (is_specialization_of<Lhs, To>) {
+    return get_optimized_expression<
+      typename Lhs::_num_, type_list_merge_sorted<typename Lhs::_den_, type_list<Rhs>, Pred>, OneType, Pred, To>();
+  } else if constexpr (is_specialization_of<Rhs, To>) {
+    return get_optimized_expression<type_list_merge_sorted<typename Rhs::_den_, type_list<Lhs>, Pred>,
+                                    typename Rhs::_num_, OneType, Pred, To>();
   } else {
     // two base dimensions
-    return To<T1, per<T2>>{};
+    return To<Lhs, per<Rhs>>{};
   }
 }
 
@@ -428,8 +428,8 @@ template<typename T1, typename T2, typename OneType, template<typename, typename
  * @tparam OneType type that represents the value `1`
  * @tparam To destination type list to put the result to
  */
-template<typename T, typename OneType, template<typename...> typename To>
-[[nodiscard]] consteval auto expr_invert()
+template<template<typename...> typename To, typename OneType, typename T>
+[[nodiscard]] consteval auto expr_invert(T)
 {
   if constexpr (is_specialization_of<T, To>)
     return expr_make_spec<typename T::_den_, typename T::_num_, OneType, To>{};
diff --git a/src/core/include/units/dimension.h b/src/core/include/units/dimension.h
index 9e17d108..561f99c2 100644
--- a/src/core/include/units/dimension.h
+++ b/src/core/include/units/dimension.h
@@ -109,8 +109,8 @@ concept Dimension = BaseDimension<T> || DerivedDimension<T>;
 
 namespace detail {
 
-template<BaseDimension D1, BaseDimension D2>
-struct base_dimension_less : std::bool_constant<(D1::symbol < D2::symbol)> {};
+template<BaseDimension Lhs, BaseDimension Rhs>
+struct base_dimension_less : std::bool_constant<(Lhs::symbol < Rhs::symbol)> {};
 
 template<typename T1, typename T2>
 using type_list_of_base_dimension_less = expr_less<T1, T2, base_dimension_less>;
@@ -249,34 +249,34 @@ using dim_type = dim_type_impl<T>::type;
 
 // Operators
 
-template<Dimension D1, Dimension D2>
-[[nodiscard]] consteval Dimension auto operator*(D1, D2)
+template<Dimension Lhs, Dimension Rhs>
+[[nodiscard]] consteval Dimension auto operator*(Lhs, Rhs)
 {
-  return detail::expr_multiply<detail::dim_type<D1>, detail::dim_type<D2>, struct one_dim,
-                               detail::type_list_of_base_dimension_less, derived_dimension>();
+  return detail::expr_multiply<derived_dimension, struct one_dim, detail::type_list_of_base_dimension_less>(
+    detail::dim_type<Lhs>{}, detail::dim_type<Rhs>{});
 }
 
-template<Dimension D1, Dimension D2>
-[[nodiscard]] consteval Dimension auto operator/(D1, D2)
+template<Dimension Lhs, Dimension Rhs>
+[[nodiscard]] consteval Dimension auto operator/(Lhs, Rhs)
 {
-  return detail::expr_divide<detail::dim_type<D1>, detail::dim_type<D2>, struct one_dim,
-                             detail::type_list_of_base_dimension_less, derived_dimension>();
+  return detail::expr_divide<derived_dimension, struct one_dim, detail::type_list_of_base_dimension_less>(
+    detail::dim_type<Lhs>{}, detail::dim_type<Rhs>{});
 }
 
 template<Dimension D>
 [[nodiscard]] consteval Dimension auto operator/(int value, D)
 {
   gsl_Assert(value == 1);
-  return detail::expr_invert<detail::dim_type<D>, struct one_dim, derived_dimension>();
+  return detail::expr_invert<derived_dimension, struct one_dim>(detail::dim_type<D>{});
 }
 
 template<Dimension D>
 [[nodiscard]] consteval Dimension auto operator/(D, int) = delete;
 
-template<Dimension D1, Dimension D2>
-[[nodiscard]] consteval bool operator==(D1, D2)
+template<Dimension Lhs, Dimension Rhs>
+[[nodiscard]] consteval bool operator==(Lhs, Rhs)
 {
-  return is_same_v<D1, D2>;
+  return is_same_v<Lhs, Rhs>;
 }
 
 template<Dimension D1, Dimension D2>