diff --git a/alib2algo/src/automaton/transform/Compaction.h b/alib2algo/src/automaton/transform/Compaction.h
index 7cf838e0384d1e4cf3eea9eadbf061f51a3ddc29..a8b872686227e750ba01f774b736b47f28a23d9a 100644
--- a/alib2algo/src/automaton/transform/Compaction.h
+++ b/alib2algo/src/automaton/transform/Compaction.h
@@ -31,6 +31,7 @@
 #include <automaton/FSM/CompactNFA.h>
 #include <automaton/FSM/NFA.h>
 #include <automaton/FSM/DFA.h>
+#include <automaton/Automaton.h>
 
 namespace automaton {
 
@@ -41,6 +42,9 @@ namespace transform {
  * The compact automaton allows to use strings in the transition function. The transitions are compacted.
  */
 class Compaction {
+	template < class T >
+	using CompactAutomaton = typename std::conditional < isDFA < T >, automaton::CompactDFA < automaton::SymbolTypeOfAutomaton < T >, automaton::StateTypeOfAutomaton < T > >, automaton::CompactNFA < automaton::SymbolTypeOfAutomaton < T >, automaton::StateTypeOfAutomaton < T > > >::type;
+
 public:
 	/**
 	 * Compaction of a finite automaton.
@@ -49,41 +53,27 @@ public:
 	 * @param automaton automaton to compact
 	 * @return compact nondeterministic FA equivalent to @p automaton
 	 */
-	template < class SymbolType, class StateType >
-	static automaton::CompactDFA < SymbolType, StateType > convert( const automaton::DFA < SymbolType, StateType > & automaton);
-
-	/**
-	 * @overload
-	 */
-	template < class SymbolType, class StateType >
-	static automaton::CompactNFA < SymbolType, StateType > convert( const automaton::NFA < SymbolType, StateType > & automaton);
-
-	/**
-	 * @overload
-	 */
-	template < class SymbolType, class StateType >
-	static automaton::CompactDFA < SymbolType, StateType > convert( const automaton::CompactDFA < SymbolType, StateType > & automaton);
+	template < class T >
+	static ext::require < isDFA < T > || isNFA < T >, Compaction::CompactAutomaton < T > > convert ( const T & automaton);
 
 	/**
 	 * @overload
 	 */
-	template < class SymbolType, class StateType >
-	static automaton::CompactNFA < SymbolType, StateType > convert( const automaton::CompactNFA < SymbolType, StateType > & automaton);
+	template < class T >
+	static ext::require < isCompactDFA < T > || isCompactNFA < T >, T > convert ( const T & automaton );
 };
 
-template < class SymbolType, class StateType >
-automaton::CompactDFA < SymbolType, StateType > Compaction::convert(const automaton::CompactDFA < SymbolType, StateType > & automaton) {
+template < class T >
+ext::require < isCompactDFA < T > || isCompactNFA < T >, T > Compaction::convert ( const T & automaton ) {
 	return automaton;
 }
 
-template < class SymbolType, class StateType >
-automaton::CompactNFA < SymbolType, StateType > Compaction::convert(const automaton::CompactNFA < SymbolType, StateType > & automaton) {
-	return automaton;
-}
+template < class T >
+ext::require < isDFA < T > || isNFA < T >, Compaction::CompactAutomaton < T > > Compaction::convert ( const T & automaton) {
+	using SymbolType = automaton::SymbolTypeOfAutomaton < T >;
+	using StateType = automaton::StateTypeOfAutomaton < T >;
 
-template < class SymbolType, class StateType >
-automaton::CompactDFA < SymbolType, StateType > Compaction::convert(const automaton::DFA < SymbolType, StateType > & automaton) {
-	automaton::CompactDFA < SymbolType, StateType > res(automaton.getInitialState());
+	CompactAutomaton < T > res(automaton.getInitialState());
 	res.setInputAlphabet(automaton.getInputAlphabet());
 
 	ext::set < ext::tuple < StateType, StateType, SymbolType > > visited;
@@ -103,7 +93,7 @@ automaton::CompactDFA < SymbolType, StateType > Compaction::convert(const automa
 
 		ext::vector < SymbolType > path { symbol };
 
-		ext::iterator_range < typename ext::map < ext::pair < StateType, SymbolType >, StateType >::const_iterator > transitions;
+		decltype ( automaton.getTransitionsFromState ( q ) ) transitions;
 		// only 1 child and nonfinal
 		while((transitions = automaton.getTransitionsFromState(q)).size() == 1 && automaton.getFinalStates().count(q) == 0) {
 			const std::pair<ext::pair<StateType, SymbolType>, StateType>& transition = * transitions.begin();
@@ -128,13 +118,6 @@ automaton::CompactDFA < SymbolType, StateType > Compaction::convert(const automa
 	return res;
 }
 
-template < class SymbolType, class StateType >
-automaton::CompactNFA < SymbolType, StateType > Compaction::convert(const automaton::NFA < SymbolType, StateType > & automaton) {
-	automaton::CompactNFA < SymbolType, StateType > res(automaton.getInitialState());
-	// TODO
-	return res;
-}
-
 } /* namespace transform */
 
 } /* namespace automaton */