Remove detail::error_handler

include/fmt/core.h

@@ -646,15 +646,6 @@ enum {
 
 // DEPRECATED!
 FMT_NORETURN FMT_API void throw_format_error(const char* message);
-
-struct error_handler {
-  constexpr error_handler() = default;
-
-  // This function is intentionally not constexpr to give a compile-time error.
-  FMT_NORETURN void on_error(const char* message) {
-    throw_format_error(message);
-  }
-};
 }  // namespace detail
 
 /** Throws ``format_error`` with a given message. */
@@ -1772,9 +1763,8 @@ template <typename OutputIt, typename Char> class basic_format_context {
   }
   auto args() const -> const format_args& { return args_; }
 
-  // DEPRECATED!
-  FMT_CONSTEXPR auto error_handler() -> detail::error_handler { return {}; }
-  void on_error(const char* message) { error_handler().on_error(message); }
+  // This function is intentionally not constexpr to give a compile-time error.
+  void on_error(const char* message) { throw_format_error(message); }
 
   // Returns an iterator to the beginning of the output range.
   FMT_CONSTEXPR auto out() -> iterator { return out_; }

include/fmt/format.h

@@ -4360,7 +4360,7 @@ void vformat_to(buffer<Char>& buf, basic_string_view<Char> fmt,
     return;
   }
 
-  struct format_handler : error_handler {
+  struct format_handler {
     basic_format_parse_context<Char> parse_context;
     buffer_context<Char> context;
 
@@ -4412,6 +4412,8 @@ void vformat_to(buffer<Char>& buf, basic_string_view<Char> fmt,
       context.advance_to(visit_format_arg(f, arg));
       return begin;
     }
+
+    void on_error(const char* message) { throw_format_error(message); }
   };
   detail::parse_format_string<false>(fmt, format_handler(out, fmt, args, loc));
 }

include/fmt/printf.h

@@ -53,9 +53,7 @@ template <typename Char> class basic_printf_context {
     return args_.get(id);
   }
 
-  FMT_CONSTEXPR void on_error(const char* message) {
-    detail::error_handler().on_error(message);
-  }
+  void on_error(const char* message) { throw_format_error(message); }
 };
 
 namespace detail {

test/scan.h

@@ -573,7 +573,7 @@ struct arg_scanner {
   }
 };
 
-struct scan_handler : error_handler {
+struct scan_handler {
  private:
   scan_parse_context parse_ctx_;
   scan_context scan_ctx_;
@@ -626,7 +626,7 @@ struct scan_handler : error_handler {
     return begin;
   }
 
-  void on_error(const char* message) { error_handler::on_error(message); }
+  void on_error(const char* message) { throw_format_error(message); }
 };
 }  // namespace detail