diff --git a/src/ast_handlers.hpp b/src/ast_handlers.hpp
new file mode 100644
index 0000000..b0d27aa
--- /dev/null
+++ b/src/ast_handlers.hpp
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2018 CESNET, https://photonics.cesnet.cz/
+ * Copyright (C) 2018 FIT CVUT, https://fit.cvut.cz/
+ *
+ * Written by Václav Kubernát <kubervac@fit.cvut.cz>
+ *
+*/
+
+#pragma once
+#include "CTree.hpp"
+
+class InvalidKeyException : public std::invalid_argument {
+public:
+    using std::invalid_argument::invalid_argument;
+    ~InvalidKeyException() override;
+};
+
+struct ParserContext {
+    ParserContext(const CTree& tree);
+    const CTree& m_tree;
+    std::string m_curPath;
+    std::string m_errorMsg;
+    std::string m_tmpListName;
+    std::set<std::string> m_tmpListKeys;
+    bool m_errorHandled = false;
+};
+
+struct keyValue_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T& ast, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        const CTree& tree = parserContext.m_tree;
+
+        if (parserContext.m_tmpListKeys.find(ast.first) != parserContext.m_tmpListKeys.end()) {
+            _pass(context) = false;
+            parserContext.m_errorMsg = "Key \"" + ast.first + "\" was entered more than once.";
+        } else if (tree.listHasKey(parserContext.m_curPath, parserContext.m_tmpListName, ast.first)) {
+            parserContext.m_tmpListKeys.insert(ast.first);
+        } else {
+            _pass(context) = false;
+            parserContext.m_errorMsg = parserContext.m_tmpListName + " is not indexed by \"" + ast.first + "\".";
+        }
+    }
+};
+struct identifier_class;
+
+struct listPrefix_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T& ast, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        const CTree& tree = parserContext.m_tree;
+
+        if (tree.isList(parserContext.m_curPath, ast)) {
+            parserContext.m_tmpListName = ast;
+        } else {
+            _pass(context) = false;
+        }
+    }
+};
+
+struct listSuffix_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T& ast, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        const CTree& tree = parserContext.m_tree;
+
+        const auto& keysNeeded = tree.listKeys(parserContext.m_curPath, parserContext.m_tmpListName);
+        std::set<std::string> keysSupplied;
+        for (const auto& it : ast)
+            keysSupplied.insert(it.first);
+
+        if (keysNeeded != keysSupplied) {
+            parserContext.m_errorMsg = "Not enough keys for " + parserContext.m_tmpListName + ". " +
+                                       "These keys were not supplied:";
+            std::set<std::string> missingKeys;
+            std::set_difference(keysNeeded.begin(), keysNeeded.end(),
+                                keysSupplied.begin(), keysSupplied.end(),
+                                std::inserter(missingKeys, missingKeys.end()));
+
+            for (const auto& it : missingKeys)
+                parserContext.m_errorMsg += " " + it;
+            parserContext.m_errorMsg += ".";
+
+            _pass(context) = false;
+        }
+    }
+};
+struct listElement_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T& ast, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        parserContext.m_curPath = joinPaths(parserContext.m_curPath, ast.m_listName);
+    }
+
+    template <typename Iterator, typename Exception, typename Context>
+    x3::error_handler_result on_error(Iterator&, Iterator const&, Exception const& ex, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        auto& error_handler = x3::get<x3::error_handler_tag>(context).get();
+        if (parserContext.m_errorHandled) // someone already handled our error
+            return x3::error_handler_result::fail;
+
+        parserContext.m_errorHandled = true;
+
+        std::string message = parserContext.m_errorMsg;
+        error_handler(ex.where(), message);
+        return x3::error_handler_result::fail;
+    }
+};
+
+struct container_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T& ast, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        const auto& tree = parserContext.m_tree;
+
+        if (tree.isContainer(parserContext.m_curPath, ast.m_name)) {
+            parserContext.m_curPath = joinPaths(parserContext.m_curPath, ast.m_name);
+        } else {
+            _pass(context) = false;
+        }
+    }
+};
+
+struct path_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T&, Context const&)
+    {
+    }
+};
+
+struct cd_class {
+    template <typename T, typename Iterator, typename Context>
+    void on_success(Iterator const&, Iterator const&, T&, Context const&)
+    {
+    }
+
+    template <typename Iterator, typename Exception, typename Context>
+    x3::error_handler_result on_error(Iterator&, Iterator const&, Exception const& x, Context const& context)
+    {
+        auto& parserContext = x3::get<parser_context_tag>(context);
+        auto& error_handler = x3::get<x3::error_handler_tag>(context).get();
+        std::string message = "This isn't a list or a container or nothing.";
+        if (parserContext.m_errorHandled) // someone already handled our error
+            return x3::error_handler_result::fail;
+
+        parserContext.m_errorHandled = true;
+        error_handler(x.where(), message);
+        return x3::error_handler_result::fail;
+    }
+};