diff --git a/include/jsoncons_ext/jsonpath/expression.hpp b/include/jsoncons_ext/jsonpath/expression.hpp
index e5ee68874..b8bd9483e 100644
--- a/include/jsoncons_ext/jsonpath/expression.hpp
+++ b/include/jsoncons_ext/jsonpath/expression.hpp
@@ -1409,7 +1409,7 @@ namespace detail {
             value_type j(json_array_arg, semantic_tag::none, alloc_);
             while (rit != rend) 
             {
-                auto s = r(*it).str();
+                auto s = (*rit).str();
                 j.emplace_back(s.c_str(), semantic_tag::none);
                 ++rit;
             }
diff --git a/include/jsoncons_ext/jsonschema/common/keyword_validators.hpp b/include/jsoncons_ext/jsonschema/common/keyword_validators.hpp
index f5b3fb811..f2517c51e 100644
--- a/include/jsoncons_ext/jsonschema/common/keyword_validators.hpp
+++ b/include/jsoncons_ext/jsonschema/common/keyword_validators.hpp
@@ -2458,7 +2458,7 @@ namespace jsonschema {
                     jsonpointer::json_pointer prop_location = instance_location / prop.key();
 
                     std::size_t errors = reporter.error_count();
-                    walk_result result = prop_(*it).second->validate(prop_context, prop.value(), prop_location, results, reporter, patch);
+                    walk_result result = (*prop_it).second->validate(prop_context, prop.value(), prop_location, results, reporter, patch);
                     if (result == walk_result::abort)
                     {
                         return result;
@@ -2525,7 +2525,7 @@ namespace jsonschema {
                 if (prop_it != properties_.end()) 
                 {
                     jsonpointer::json_pointer prop_location = instance_location / prop.key();
-                    result = prop_(*it).second->walk(context, prop.value(), prop_location, reporter);
+                    result = (*prop_it).second->walk(context, prop.value(), prop_location, reporter);
                     allowed_properties.insert(prop.key());
                     if (result == walk_result::abort)
                     {
diff --git a/include/jsoncons_ext/jsonschema/draft201909/schema_builder_201909.hpp b/include/jsoncons_ext/jsonschema/draft201909/schema_builder_201909.hpp
index b04e8042b..870f9e85e 100644
--- a/include/jsoncons_ext/jsonschema/draft201909/schema_builder_201909.hpp
+++ b/include/jsoncons_ext/jsonschema/draft201909/schema_builder_201909.hpp
@@ -411,7 +411,7 @@ namespace draft201909 {
                     auto factory_it = validation_factory_map_.find(key_value.key());
                     if (factory_it != validation_factory_map_.end())
                     {
-                        auto validator = factory_(*it).second(context, key_value.value(), sch, anchor_dict);
+                        auto validator = (*factory_it).second(context, key_value.value(), sch, anchor_dict);
                         if (validator)
                         {   
                             validators.emplace_back(std::move(validator));
diff --git a/include/jsoncons_ext/jsonschema/draft202012/schema_builder_202012.hpp b/include/jsoncons_ext/jsonschema/draft202012/schema_builder_202012.hpp
index 60eb2c507..01415b04d 100644
--- a/include/jsoncons_ext/jsonschema/draft202012/schema_builder_202012.hpp
+++ b/include/jsoncons_ext/jsonschema/draft202012/schema_builder_202012.hpp
@@ -418,7 +418,7 @@ namespace draft202012 {
                     auto factory_it = validation_factory_map_.find(key_value.key());
                     if (factory_it != validation_factory_map_.end())
                     {
-                        auto validator = factory_(*it).second(context, key_value.value(), sch, local_anchor_dict);
+                        auto validator = (*factory_it).second(context, key_value.value(), sch, local_anchor_dict);
                         if (validator)
                         {   
                             validators.emplace_back(std::move(validator));
diff --git a/include/jsoncons_ext/jsonschema/draft4/schema_builder_4.hpp b/include/jsoncons_ext/jsonschema/draft4/schema_builder_4.hpp
index 6139a7c40..f31204297 100644
--- a/include/jsoncons_ext/jsonschema/draft4/schema_builder_4.hpp
+++ b/include/jsoncons_ext/jsonschema/draft4/schema_builder_4.hpp
@@ -216,7 +216,7 @@ namespace draft4 {
                 auto factory_it = keyword_factory_map_.find(key_value.key());
                 if (factory_it != keyword_factory_map_.end())
                 {
-                    auto validator = factory_(*it).second(context, key_value.value(), sch, anchor_dict);
+                    auto validator = (*factory_it).second(context, key_value.value(), sch, anchor_dict);
                     if (validator)
                     {   
                         validators.emplace_back(std::move(validator));
diff --git a/include/jsoncons_ext/jsonschema/draft6/schema_builder_6.hpp b/include/jsoncons_ext/jsonschema/draft6/schema_builder_6.hpp
index 0e50a8640..43e8ffc1c 100644
--- a/include/jsoncons_ext/jsonschema/draft6/schema_builder_6.hpp
+++ b/include/jsoncons_ext/jsonschema/draft6/schema_builder_6.hpp
@@ -227,7 +227,7 @@ namespace draft6 {
                 auto factory_it = keyword_factory_map_.find(key_value.key());
                 if (factory_it != keyword_factory_map_.end())
                 {
-                    auto validator = factory_(*it).second(context, key_value.value(), sch, anchor_dict);
+                    auto validator = (*factory_it).second(context, key_value.value(), sch, anchor_dict);
                     if (validator)
                     {   
                         validators.emplace_back(std::move(validator));
diff --git a/include/jsoncons_ext/jsonschema/draft7/schema_builder_7.hpp b/include/jsoncons_ext/jsonschema/draft7/schema_builder_7.hpp
index 7ec5709dd..1786709de 100644
--- a/include/jsoncons_ext/jsonschema/draft7/schema_builder_7.hpp
+++ b/include/jsoncons_ext/jsonschema/draft7/schema_builder_7.hpp
@@ -229,7 +229,7 @@ namespace draft7 {
                 auto factory_it = keyword_factory_map_.find(key_value.key());
                 if (factory_it != keyword_factory_map_.end())
                 {
-                    auto validator = factory_(*it).second(context, key_value.value(), sch, anchor_dict);
+                    auto validator = (*factory_it).second(context, key_value.value(), sch, anchor_dict);
                     if (validator)
                     {   
                         validators.emplace_back(std::move(validator));
diff --git a/include/jsoncons_ext/jsonschema/json_schema_factory.hpp b/include/jsoncons_ext/jsonschema/json_schema_factory.hpp
index 7e2e2e5d1..92d2c5922 100644
--- a/include/jsoncons_ext/jsonschema/json_schema_factory.hpp
+++ b/include/jsoncons_ext/jsonschema/json_schema_factory.hpp
@@ -160,7 +160,7 @@ namespace jsonschema {
                     auto vocab_it = meta_sch.find("$vocabulary");
                     if (vocab_it != meta_sch.object_range().end())
                     {
-                        const auto& vocab = vocab_(*it).value();
+                        const auto& vocab = (*vocab_it).value();
                         if (vocab.is_object())
                         {
                             for (const auto& member : vocab.object_range())
@@ -172,7 +172,7 @@ namespace jsonschema {
                     auto schema_it = meta_sch.find("$schema");
                     if (schema_it != meta_sch.object_range().end())
                     {
-                        builder = get_builder(std::move(sch), schema_(*it).value().as_string_view(), options, schema_store_ptr, resolve_funcs, vocabulary);
+                        builder = get_builder(std::move(sch), (*schema_it).value().as_string_view(), options, schema_store_ptr, resolve_funcs, vocabulary);
                         found = true;
                     }
                 }