re-use lamdas definitions and aviod duplicate symbols when building with vs2017

include/mapnik/json/feature_grammar_x3_def.hpp

@@ -164,15 +164,6 @@ struct geometry_type_ : x3::symbols<mapnik::geometry::geometry_types>
     }
 } geometry_type_symbols;
 
-auto assign_name = [](auto const& ctx)
-{
-    std::get<0>(_val(ctx)) = std::move(_attr(ctx));
-};
-auto assign_value = [](auto const& ctx)
-{
-    std::get<1>(_val(ctx)) = std::move(_attr(ctx));
-};
-
 auto const assign_geometry_type = [] (auto const& ctx)
 {
     std::get<0>(_val(ctx)) = _attr(ctx);
@@ -263,7 +254,7 @@ auto const geometry_tuple_def = (geometry_type[assign_geometry_type]
                                  (omit[geojson_string] > lit(':') > omit[value])) % lit(',');
 
 
-auto const property_def = geojson_string[assign_name] > lit(':') > value[assign_value];
+auto const property_def = geojson_string[assign_key] > lit(':') > value[assign_value];
 
 auto const properties_def = property[assign_property] % lit(',');
 

include/mapnik/json/generic_json_grammar_x3.hpp

@@ -43,6 +43,21 @@ BOOST_SPIRIT_DECLARE(generic_json_grammar_type);
 BOOST_SPIRIT_DECLARE(generic_json_key_value_type);
 }
 
+auto assign = [](auto const& ctx)
+{
+    _val(ctx) = _attr(ctx);
+};
+
+auto assign_key = [](auto const& ctx)
+{
+    std::get<0>(_val(ctx)) = _attr(ctx);
+};
+
+auto assign_value = [](auto const& ctx)
+{
+    std::get<1>(_val(ctx)) = std::move(_attr(ctx));
+};
+
 grammar::generic_json_grammar_type const& generic_json_grammar();
 grammar::generic_json_key_value_type const& generic_json_key_value();
 

include/mapnik/json/generic_json_grammar_x3_def.hpp

@@ -46,22 +46,6 @@ auto make_false = [] (auto const& ctx)
     _val(ctx) = false;
 };
 
-auto assign = [](auto const& ctx)
-{
-    _val(ctx) = _attr(ctx);
-};
-
-auto assign_key = [](auto const& ctx)
-{
-    std::get<0>(_val(ctx)) = _attr(ctx);
-};
-
-auto assign_value = [](auto const& ctx)
-{
-    std::get<1>(_val(ctx)) = _attr(ctx);
-};
-
-
 using x3::lit;
 using x3::string;
 // exported rules