Improve exception handling.

Author: ColinH

include/tao/json/internal/action.hpp

@@ -138,7 +138,7 @@ namespace tao
             static void apply( const Input& in, number_state& result )
             {
                if( in.size() > ( 1 << 20 ) ) {
-                  throw json_pegtl::parse_error( "JSON number with 1 megabyte digits", in );
+                  throw std::runtime_error( "JSON number with 1 megabyte digits" );
                }
                const auto c = std::min( in.size(), max_mantissa_digits );
                std::memcpy( result.mantissa, in.begin(), c );
@@ -202,7 +202,7 @@ namespace tao
                   ++b;
                }
                if( ( in.end() - b ) > 9 ) {
-                  throw json_pegtl::parse_error( "JSON exponent has more than 9 significant digits", in );
+                  throw std::runtime_error( "JSON exponent has more than 9 significant digits" );
                }
                int exponent10 = 0;
 

include/tao/json/internal/control.hpp

@@ -26,17 +26,17 @@ namespace tao
          };
 
          template<>
-         struct control< rules::number > : json_pegtl::change_state< rules::number, number_state, json_pegtl::normal >
+         struct control< rules::number > : json_pegtl::change_state< rules::number, number_state, errors >
          {
          };
 
          template<>
-         struct control< rules::string::content > : json_pegtl::change_state_and_action< rules::string::content, string_state, unescape_action, json_pegtl::normal >
+         struct control< rules::string::content > : json_pegtl::change_state_and_action< rules::string::content, string_state, unescape_action, errors >
          {
          };
 
          template<>
-         struct control< rules::key::content > : json_pegtl::change_state_and_action< rules::key::content, key_state, unescape_action, json_pegtl::normal >
+         struct control< rules::key::content > : json_pegtl::change_state_and_action< rules::key::content, key_state, unescape_action, errors >
          {
          };
 

include/tao/json/internal/errors.hpp

@@ -36,6 +36,36 @@ namespace tao
             {
                throw json_pegtl::parse_error( error_message, in );
             }
+
+            template< template< typename... > class Action, typename Input, typename... States >
+            static void apply0( const Input& in, States&&... st )
+            {
+               try {
+                  Action< Rule >::apply0( st... );
+               }
+               catch( const json_pegtl::parse_error& ) {
+                  throw;
+               }
+               catch( const std::exception& e ) {
+                  throw json_pegtl::parse_error( e.what(), in );
+               }
+            }
+
+            template< template< typename... > class Action, typename Iterator, typename Input, typename... States >
+            static void apply( const Iterator begin, const Iterator end, const Input& in, States&&... st )
+            {
+               try {
+                  using action_t = typename Input::action_t;
+                  const action_t action_input( begin, end, in.source() );
+                  Action< Rule >::apply( action_input, st... );
+               }
+               catch( const json_pegtl::parse_error& ) {
+                  throw;
+               }
+               catch( const std::exception& e ) {
+                  throw json_pegtl::parse_error( e.what(), in );
+               }
+            }
          };
 
          // clang-format off