remove std::format

Author: MarcelloPerathoner

src/extractor/area/area_mesher.cpp

@@ -24,7 +24,6 @@
 #include <osmium/osm/types.hpp>
 
 #include <algorithm>
-#include <format>
 #include <iterator>
 
 namespace osrm::extractor::area
@@ -62,8 +61,9 @@ void copy_tags(osmium::builder::Builder &parent, const osmium::TagList &tags)
  */
 std::string area_id(const osmium::Area &area)
 {
-    char type = area.id() % 2 == 1 ? 'r' : 'w';
-    return std::format("{}{}", type, area.orig_id());
+    std::stringstream strstream;
+    strstream << (area.id() % 2 == 1 ? "r" : "w") << area.orig_id();
+    return strstream.str();
 }
 
 } // namespace
@@ -302,11 +302,12 @@ void AreaMesher::mesh_area(const osmium::Area &area,
         out_buffer.commit();
     };
 
-    const auto write_debug = [&](const char *filename, const std::set<OsmiumSegment> &segments)
+    const auto write_debug = [&](const char *basename, const std::set<OsmiumSegment> &segments)
     {
         // write debug file
-        std::filesystem::path path = std::filesystem::temp_directory_path() /
-                                     std::format("{}-{}.osm", filename, area_id(area));
+        std::stringstream strstream;
+        strstream << basename << "-" << area_id(area) << ".osm";
+        std::filesystem::path path = std::filesystem::temp_directory_path() / strstream.str();
         osmium::io::Writer writer(path, osmium::io::overwrite::allow);
         osmium::memory::Buffer debug_buffer{16 * 1024};
         add_to_buffer(segments, debug_buffer);