From 958b5a756e482b368b362ef1fbebbdae3fd59652 Mon Sep 17 00:00:00 2001
From: Andreas Wass <andreas.wass@dalelven.com>
Date: Thu, 2 Nov 2017 11:09:49 +0100
Subject: [PATCH] Fix g++ compilation errors

---
 fmt/format.h | 85 ++++++++++++++++++++++++++++++++--------------------
 1 file changed, 52 insertions(+), 33 deletions(-)

diff --git a/fmt/format.h b/fmt/format.h
index ba6c8935..89d9a6c9 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -4086,67 +4086,86 @@ void format_arg(fmt::BasicFormatter<Char, ArgFormatter> &f,
   format_str = end + 1;
 }
 
-struct ArgConcatNoSeparator
-{
+struct ArgConcatNoSeparator {
+    template<typename ArgFormatter>
+    void add_separator(fmt::BasicFormatter<char, ArgFormatter>&) const {}
+
+    template<typename ArgFormatter>
+    void add_separator(fmt::BasicFormatter<wchar_t, ArgFormatter>&) const {}
 };
 
 template<typename Char>
 struct ArgConcatSeparator {
     BasicCStringRef<Char> sep;
+    ArgConcatSeparator(const BasicCStringRef<Char> &sep): sep(sep) {}
+    template<typename ArgFormatter>
+    void add_separator(fmt::BasicFormatter<Char, ArgFormatter> &f) const {
+        f.writer().write(sep);
+    }
 };
 
 template<typename Separator, typename ...Args>
-struct ArgConcat: public Separator {
-    std::tuple<Args...> a;
-    ArgConcat(const Separator &sep, Args&&...args):
-        Separator(sep), a(std::forward<Args>(args)...){
+struct ArgConcat {
+};
+
+template<typename Separator>
+struct ArgConcat<Separator>: public Separator {
+
+    ArgConcat(const Separator &sep): Separator(sep) {}
+
+    template<typename Char, typename ArgFormatter>
+    void format(fmt::BasicFormatter<Char, ArgFormatter> &,
+                const Char *&) const {
     }
 
-    template<std::size_t I, typename Char, typename ArgFormatter>
-    std::enable_if_t<I == sizeof...(Args), void>
-    format(fmt::BasicFormatter<Char, ArgFormatter> &,
-           const Char *&) const {
+    template<typename Char, typename ArgFormatter>
+    void format_first(fmt::BasicFormatter<Char, ArgFormatter> &,
+                const Char *&) const {
+    }
+};
+
+template<typename Separator, typename A, typename ...Args>
+struct ArgConcat<Separator, A, Args...>: public ArgConcat<Separator, Args...> {
+    A a;
+
+    ArgConcat(const Separator &sep, A a, Args...args):
+        ArgConcat<Separator, Args...>(sep, args...),
+        a(a){
     }
 
-    template<std::size_t I, typename Char, typename ArgFormatter>
-    std::enable_if_t<I < sizeof...(Args) &&
-    std::is_same<Separator, ArgConcatNoSeparator>::value, void>
-    format(fmt::BasicFormatter<Char, ArgFormatter> &f,
+    template<typename Char, typename ArgFormatter>
+    void format(fmt::BasicFormatter<Char, ArgFormatter> &f,
            const Char *&format_str) const {
         const Char* save = format_str;
+        this->add_separator(f);
         f.format(format_str,
-                 internal::MakeArg<fmt::BasicFormatter<Char, ArgFormatter> >(std::get<I>(a)));
-        format<I+1>(f, save);
+                 internal::MakeArg<fmt::BasicFormatter<Char, ArgFormatter> >(a));
+        ArgConcat<Separator, Args...>::format(f, save);
     }
 
-    template<std::size_t I, typename Char, typename ArgFormatter>
-    std::enable_if_t<I < sizeof...(Args) &&
-        std::is_same<Separator,ArgConcatSeparator<Char>>::value, void>
-    format(fmt::BasicFormatter<Char, ArgFormatter> &f,
-           const Char *&format_str) const {
+    template<typename Char, typename ArgFormatter>
+    void format_first(fmt::BasicFormatter<Char, ArgFormatter> &f,
+                      const Char *&format_str) const {
         const Char* save = format_str;
-        if(I != 0) {
-            f.writer().write(Separator::sep);
-        }
         f.format(format_str,
-                 internal::MakeArg<fmt::BasicFormatter<Char, ArgFormatter> >(std::get<I>(a)));
-        format<I+1>(f, save);
+                 internal::MakeArg<fmt::BasicFormatter<Char, ArgFormatter> >(a));
+        ArgConcat<Separator, Args...>::format(f, save);
     }
 };
 
 template<typename ...Args>
-ArgConcat<ArgConcatNoSeparator, Args...> concat(Args&&...args) {
-    return ArgConcat<ArgConcatNoSeparator, Args...>{ArgConcatNoSeparator{}, std::forward<Args>(args)...};
+ArgConcat<ArgConcatNoSeparator, Args...> concat(Args...args) {
+    return ArgConcat<ArgConcatNoSeparator, Args...>(ArgConcatNoSeparator(), args...);
 }
 
 template<typename ...Args>
-ArgConcat<ArgConcatSeparator<char>, Args...> concat_separated(const BasicCStringRef<char> &sep, Args&&...args) {
-    return ArgConcat<ArgConcatSeparator<char>, Args...>{ArgConcatSeparator<char>{sep}, std::forward<Args>(args)...};
+ArgConcat<ArgConcatSeparator<char>, Args...> concat_separated(const BasicCStringRef<char> &sep, Args...args) {
+    return ArgConcat<ArgConcatSeparator<char>, Args...>(ArgConcatSeparator<char>(sep), args...);
 }
 
 template<typename ...Args>
-ArgConcat<ArgConcatSeparator<wchar_t>, Args...> concat_separated(const BasicCStringRef<wchar_t> &sep, Args&&...args) {
-    return ArgConcat<ArgConcatSeparator<wchar_t>, Args...>{ArgConcatSeparator<wchar_t>{sep}, std::forward<Args>(args)...};
+ArgConcat<ArgConcatSeparator<wchar_t>, Args...> concat_separated(const BasicCStringRef<wchar_t> &sep, Args...args) {
+    return ArgConcat<ArgConcatSeparator<wchar_t>, Args...>(ArgConcatSeparator<wchar_t>(sep), args...);
 }
 
 template<typename ArgFormatter, typename Char, typename Separator, typename ...Args>
@@ -4160,7 +4179,7 @@ void format_arg(fmt::BasicFormatter<Char, ArgFormatter> &f,
     if (*end != '}')
       FMT_THROW(FormatError("missing '}' in format string"));
 
-    e.format<0>(f, format_str);
+    e.format_first(f, format_str);
     format_str = end + 1;
 }
 }  // namespace fmt