Index: libcfa/src/bits/sequence.hfa
===================================================================
--- libcfa/src/bits/sequence.hfa	(revision 7c1144b7727d250b3c8701afbc8ac36213ac407a)
+++ libcfa/src/bits/sequence.hfa	(revision e91a255f5dee71cf7d5765c7741c5147db2d26e2)
@@ -31,8 +31,4 @@
 			return (T *)Back( (Seqable *)&n );
 		}
-
-		T & head( Sequence(T) & s ) with( s ) {
-			return *(T *)head( (Collection &)s );
-		} // post: empty() & head() == 0 | !empty() & head() in *s
 	} // distribution
 } // distribution
@@ -44,4 +40,9 @@
 
 	inline {
+		// wrappers to make Collection have T
+		T & head( Sequence(T) & s ) with( s ) {
+			return *(T *)head( (Collection &)s );
+		} // post: empty() & head() == 0 | !empty() & head() in *s
+
 		void ?{}( Sequence(T) &, const Sequence(T) & ) = void; // no copy
 		Sequence(T) & ?=?( const Sequence(T) & ) = void; // no assignment