Migrate prefixes to Magnitude

src/core/include/units/bits/basic_concepts.h

@@ -40,11 +40,11 @@ namespace units {
 // Prefix
 namespace detail {
 
-template<ratio R>
+template<Magnitude auto M>
 struct prefix_base;
 
-template<ratio R>
-void to_prefix_base(const volatile prefix_base<R>*);
+template<Magnitude auto M>
+void to_prefix_base(const volatile prefix_base<M>*);
 
 }  // namespace detail
 

src/core/include/units/bits/unit_text.h

@@ -69,28 +69,22 @@ constexpr auto magnitude_text()
   }
 }
 
-template<ratio R>
-constexpr auto ratio_text()
+template<Unit U, Magnitude auto M, std::size_t SymbolLen>
+constexpr auto prefix_or_magnitude_text()
 {
-  return magnitude_text<as_magnitude<R>()>();
-}
-
-template<Unit U, ratio R, std::size_t SymbolLen>
-constexpr auto prefix_or_ratio_text()
-{
-  if constexpr (R.num == 1 && R.den == 1 && R.exp == 0) {
+  if constexpr (M == as_magnitude<1>()) {
     // no ratio/prefix
     return basic_fixed_string("");
   } else {
     // try to form a prefix
-    using prefix = downcast<detail::prefix_base<R>>;
+    using prefix = downcast<detail::prefix_base<M>>;
 
-    if constexpr (can_be_prefixed<U> && !is_same_v<prefix, prefix_base<R>>) {
+    if constexpr (can_be_prefixed<U> && !is_same_v<prefix, prefix_base<M>>) {
       // print as a prefixed unit
       return prefix::symbol;
     } else {
       // print as a ratio of the coherent unit
-      constexpr auto txt = ratio_text<R>();
+      constexpr auto txt = magnitude_text<M>();
       if constexpr (SymbolLen > 0 && txt.standard().size() > 0)
         return txt + basic_fixed_string(" ");
       else
@@ -164,7 +158,7 @@ constexpr auto unit_text()
     }();
 
     constexpr auto prefix_txt =
-      prefix_or_ratio_text<U, as_ratio(U::mag / coherent_unit::mag), symbol_text.standard().size()>();
+      prefix_or_magnitude_text<U, U::mag / coherent_unit::mag, symbol_text.standard().size()>();
     return prefix_txt + symbol_text;
   }
 }

src/core/include/units/prefix.h

@@ -34,9 +34,9 @@ namespace units {
 
 namespace detail {
 
-template<ratio R>
-struct prefix_base : downcast_base<prefix_base<R>> {
-  static constexpr UNITS_MSVC_WORKAROUND(Magnitude) auto mag = as_magnitude<R>();
+template<Magnitude auto M>
+struct prefix_base : downcast_base<prefix_base<M>> {
+  static constexpr UNITS_MSVC_WORKAROUND(Magnitude) auto mag = M;
 };
 
 }  // namespace detail
@@ -54,8 +54,8 @@ struct prefix_base : downcast_base<prefix_base<R>> {
  * @tparam Symbol a text representation of the prefix
  * @tparam R factor to be used to scale a unit
  */
-template<typename Child, basic_symbol_text Symbol, ratio R>
-struct prefix : downcast_dispatch<Child, detail::prefix_base<R>, downcast_mode::on> {
+template<typename Child, basic_symbol_text Symbol, Magnitude auto M>
+struct prefix : downcast_dispatch<Child, detail::prefix_base<M>, downcast_mode::on> {
   static constexpr auto symbol = Symbol;
 };