Seems we finally get pack indexing, see https://groups.google.com/a/i…

…socpp.org/g/std-proposals/c/ajLcDl8GbpA/m/woiAbredAwAJ
taocpp · May 21, 2024 · bbd855d · bbd855d
1 parent 21df9f3
commit bbd855d
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diff --git a/include/tao/pq/table_writer.hpp b/include/tao/pq/table_writer.hpp
@@ -8,7 +8,9 @@
 #include <memory>
 #include <string>
 #include <string_view>
+#if !defined( __cpp_pack_indexing )
 #include <tuple>
+#endif
 #include <type_traits>
 #include <utility>
 
@@ -25,6 +27,28 @@ namespace tao::pq
       std::shared_ptr< transaction > m_previous;
       std::shared_ptr< transaction > m_transaction;
 
+#if defined( __cpp_pack_indexing )
+
+      template< std::size_t... Os, std::size_t... Is, typename... Ts >
+      void insert_indexed( std::index_sequence< Os... > /*unused*/,
+                           std::index_sequence< Is... > /*unused*/,
+                           const Ts...& ts )
+      {
+         std::string buffer;
+         ( ( ts...[ Os ].template copy_to< Is >( buffer ), buffer += '\t' ), ... );
+         *buffer.rbegin() = '\n';
+         table_writer::insert_raw( buffer );
+      }
+
+      template< typename... Ts >
+      void insert_traits( const Ts&... ts )
+      {
+         using gen = internal::gen< Ts::columns... >;
+         table_writer::insert_indexed( typename gen::outer_sequence(), typename gen::inner_sequence(), ts... );
+      }
+
+#else
+
       template< std::size_t... Os, std::size_t... Is, typename... Ts >
       void insert_indexed( std::index_sequence< Os... > /*unused*/,
                            std::index_sequence< Is... > /*unused*/,
@@ -43,6 +67,8 @@ namespace tao::pq
          table_writer::insert_indexed( typename gen::outer_sequence(), typename gen::inner_sequence(), std::tie( ts... ) );
       }
 
+#endif
+
       void check_result();
 
    public:

diff --git a/include/tao/pq/transaction.hpp b/include/tao/pq/transaction.hpp
@@ -10,7 +10,9 @@
 #include <cstdio>
 #include <memory>
 #include <string>
+#if !defined( __cpp_pack_indexing )
 #include <tuple>
+#endif
 #include <type_traits>
 #include <utility>
 
@@ -66,6 +68,30 @@ namespace tao::pq
                         const int lengths[],
                         const int formats[] );
 
+#if defined( __cpp_pack_indexing )
+
+      template< std::size_t... Os, std::size_t... Is, typename... Ts >
+      void send_indexed( const char* statement,
+                         std::index_sequence< Os... > /*unused*/,
+                         std::index_sequence< Is... > /*unused*/,
+                         const Ts...& ts )
+      {
+         const Oid types[] = { static_cast< Oid >( ts...[ Os ].template type< Is >() )... };
+         const char* const values[] = { ts...[ Os ].template value< Is >()... };
+         const int lengths[] = { ts...[ Os ].template length< Is >()... };
+         const int formats[] = { ts...[ Os ].template format< Is >()... };
+         send_params( statement, sizeof...( Os ), types, values, lengths, formats );
+      }
+
+      template< typename... Ts >
+      void send_traits( const char* statement, const Ts&... ts )
+      {
+         using gen = internal::gen< Ts::columns... >;
+         transaction::send_indexed( statement, typename gen::outer_sequence(), typename gen::inner_sequence(), ts... );
+      }
+
+#else
+
       template< std::size_t... Os, std::size_t... Is, typename... Ts >
       void send_indexed( const char* statement,
                          std::index_sequence< Os... > /*unused*/,
@@ -86,6 +112,8 @@ namespace tao::pq
          transaction::send_indexed( statement, typename gen::outer_sequence(), typename gen::inner_sequence(), std::tie( ts... ) );
       }
 
+#endif
+
    public:
       [[nodiscard]] auto connection() const noexcept -> const std::shared_ptr< pq::connection >&
       {