Improve error message when a node processor is not defined yet

src/language/ASTNodeExpressionBuilder.cpp

@@ -133,7 +133,7 @@ ASTNodeExpressionBuilder::_buildExpression(ASTNode& n)
     n.m_node_processor = std::make_unique<ContinueProcessor>();
   } else {
     std::ostringstream error_message;
-    error_message << "undefined node type '" << rang::fgB::red << n.name() << rang::fg::reset << "'";
+    error_message << "undefined node processor type '" << rang::fgB::red << n.name() << rang::fg::reset << "'";
     throw parse_error{error_message.str(), std::vector{n.begin()}};
   }