mark format methods const

Author: arBmind

src/enum19.lib/enum19/Enum.fmt.h

@@ -9,7 +9,7 @@
 template<enum19::HasMetaEnum T, class Char> struct fmt::formatter<T, Char> {
     constexpr auto parse(fmt::basic_format_parse_context<Char>& ctx) { return ctx.begin(); }
 
-    template<typename FormatCtx> auto format(const T& v, FormatCtx& ctx) {
+    template<typename FormatCtx> auto format(const T& v, FormatCtx& ctx) const {
         auto underlying = static_cast<std::underlying_type_t<T>>(v);
         return fmt::format_to(ctx.out(), "{} ({})", enum19::valueName(v), underlying);
     }

src/string19.lib/string19/StringView.fmt.h

@@ -7,7 +7,7 @@
 template<class Char> struct fmt::formatter<string19::StringView, Char> {
     constexpr auto parse(fmt::basic_format_parse_context<Char>& ctx) { return ctx.begin(); }
 
-    template<typename FormatContext> auto format(const string19::StringView& v, FormatContext& ctx) {
+    template<typename FormatContext> auto format(const string19::StringView& v, FormatContext& ctx) const {
         auto out = ctx.out();
         for (auto i = 0u; i < v.count; i++) *out++ = v[i];
         return out;

src/strong19.lib/strong19/Strong.fmt.h

@@ -9,7 +9,7 @@
 template<class T, class Char> requires(strong19::is_strong<T>) struct fmt::formatter<T, Char> {
     constexpr auto parse(fmt::basic_format_parse_context<Char>& ctx) { return ctx.begin(); }
 
-    template<typename FormatContext> auto format(const T& v, FormatContext& ctx) {
+    template<typename FormatContext> auto format(const T& v, FormatContext& ctx) const {
         return fmt::format_to(ctx.out(), "{}{{{}}}", strong19::strong_name<T>, v.v);
     }
 };

src/tuple19.lib/tuple19/Tuple.fmt.h

@@ -12,16 +12,15 @@ namespace tuple19 {
 template<class... Ts> constexpr auto make_format_args(Tuple<Ts...> const& args) {
     return [&]<size_t... Is>(std::index_sequence<Is...> const&) {
         return fmt::make_format_args(args.template at<Is>()...);
-    }
-    (std::make_index_sequence<sizeof...(Ts)>{});
+    }(std::make_index_sequence<sizeof...(Ts)>{});
 }
 
 } // namespace tuple19
 
 template<class... Ts, class Char> struct fmt::formatter<tuple19::Tuple<Ts...>, Char> {
     constexpr auto parse(fmt::basic_format_parse_context<Char>& ctx) { return ctx.begin(); }
 
-    template<typename FormatContext> auto format(tuple19::Tuple<Ts...> const& v, FormatContext& ctx) {
+    template<typename FormatContext> auto format(tuple19::Tuple<Ts...> const& v, FormatContext& ctx) const {
         if constexpr (sizeof...(Ts) == 0) {
             return fmt::format_to(ctx.out(), "Tuple<>");
         }
@@ -30,8 +29,7 @@ template<class... Ts, class Char> struct fmt::formatter<tuple19::Tuple<Ts...>, C
                 auto out = fmt::format_to(ctx.out(), "{}", v.template at<0>());
                 ((out = fmt::format_to(out, ", {}", v.template at<Is>())), ...);
                 return out;
-            }
-            (std::make_index_sequence<sizeof...(Ts)>{});
+            }(std::make_index_sequence<sizeof...(Ts)>{});
         }
     }
 };