From 92477b7e5b1017d532cf1a30e3293681f2e8ce80 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Sat, 27 Apr 2024 11:52:07 -0400
Subject: [PATCH] xo-ratio: refactor: rename ratio.to<> -> ratio.convert_to<>

---
 include/xo/ratio/ratio.hpp | 28 ++++++++++++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/include/xo/ratio/ratio.hpp b/include/xo/ratio/ratio.hpp
index 1acbb74..2c4b0c5 100644
--- a/include/xo/ratio/ratio.hpp
+++ b/include/xo/ratio/ratio.hpp
@@ -24,12 +24,17 @@ namespace xo {
             /** @brief promote value to ratio type **/
             template <typename Ratio, typename FromType, bool FromRatioFlag = ratio_concept<FromType>>
             struct promoter_type;
+
+            /** @brief convert value to different numeric (or ratio) representation **/
+            template <typename Ratio, typename ToType, bool ToRatioFlag = ratio_concept<ToType>>
+            struct converter_type;
         }
 
         /** @class ratio
          *  @brief represent a ratio of two Int values.
          **/
-        template <typename Int> requires std::totally_ordered<Int>
+        template <typename Int>
+        requires std::totally_ordered<Int>
         struct ratio
         {
         public:
@@ -255,7 +260,9 @@ namespace xo {
              *  For example: to int or double
              **/
             template <typename Repr>
-            constexpr Repr to() const noexcept { return num_ / static_cast<Repr>(den_); }
+            constexpr Repr convert_to() const noexcept {
+                return detail::converter_type<ratio, Repr>::convert(*this);
+            }
 
             /** @brief convert to short human-friendly flatstring representation
              *
@@ -361,6 +368,23 @@ namespace xo {
             };
         }
 
+        namespace detail {
+            template <typename Ratio, typename ToType, bool ToRatioFlag>
+            struct converter_type;
+
+            template <typename Ratio, typename ToType>
+            struct converter_type<Ratio, ToType, true /*ToRatioFlag*/> {
+                /* to convert to a ratio,  can just use built-in conversion */
+                static constexpr ToType convert(Ratio x) { return ToType(x.num(), x.den()); }
+            };
+
+            template <typename Ratio, typename ToType>
+            struct converter_type<Ratio, ToType, false /*!ToRatioFlag*/> {
+                /* to convert to non-ratio,  do division */
+                static constexpr ToType convert(Ratio x) { return x.num() / static_cast<ToType>(x.den()); }
+            };
+        }
+
         /** @brief create a ratio in lowest terms from two integers **/
         template <typename Int1, typename Int2>
         constexpr auto