From b3fb025053bb06ee1d044690dc5f268042231f9d Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Mon, 4 Sep 2023 11:15:33 +0200
Subject: [PATCH] feat(example): text output added to `validated_type` and
 `ranged_representation`

---
 example/include/ranged_representation.h | 10 ++++++++++
 example/include/validated_type.h        | 21 +++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/example/include/ranged_representation.h b/example/include/ranged_representation.h
index 60bab6fe..d0a725a9 100644
--- a/example/include/ranged_representation.h
+++ b/example/include/ranged_representation.h
@@ -24,6 +24,7 @@
 
 #include "validated_type.h"
 #include <mp-units/bits/external/hacks.h>
+#include <mp-units/bits/fmt.h>
 #include <mp-units/customization_points.h>
 #include <algorithm>
 #include <concepts>
@@ -53,3 +54,12 @@ public:
 
 template<typename T, auto Min, auto Max>
 inline constexpr bool mp_units::is_scalar<ranged_representation<T, Min, Max>> = mp_units::is_scalar<T>;
+
+template<typename T, auto Min, auto Max>
+struct MP_UNITS_STD_FMT::formatter<ranged_representation<T, Min, Max>> : formatter<T> {
+  template<typename FormatContext>
+  auto format(const ranged_representation<T, Min, Max>& v, FormatContext& ctx)
+  {
+    return formatter<T>::format(v.value(), ctx);
+  }
+};
diff --git a/example/include/validated_type.h b/example/include/validated_type.h
index 8692a9b3..2cf8cc71 100644
--- a/example/include/validated_type.h
+++ b/example/include/validated_type.h
@@ -24,6 +24,8 @@
 
 #include <gsl/gsl-lite.hpp>
 #include <mp-units/bits/external/hacks.h>
+#include <mp-units/bits/fmt.h>
+#include <ostream>
 #include <utility>
 
 inline constexpr struct validated_tag {
@@ -97,3 +99,22 @@ public:
     requires std::three_way_comparable<T>
   = default;
 };
+
+
+template<typename CharT, typename Traits, typename T, typename Validator>
+std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os,
+                                              const validated_type<T, Validator>& v)
+  requires requires { os << v.value(); }
+{
+  return os << v.value();
+}
+
+
+template<typename T, typename Validator>
+struct MP_UNITS_STD_FMT::formatter<validated_type<T, Validator>> : formatter<T> {
+  template<typename FormatContext>
+  auto format(const validated_type<T, Validator>& v, FormatContext& ctx)
+  {
+    return formatter<T>::format(v.value(), ctx);
+  }
+};