Index: /trunk/src/org/openstreetmap/josm/data/osm/search/SearchCompiler.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/osm/search/SearchCompiler.java	(revision 16258)
+++ /trunk/src/org/openstreetmap/josm/data/osm/search/SearchCompiler.java	(revision 16259)
@@ -18,4 +18,6 @@
 import java.util.Objects;
 import java.util.Optional;
+import java.util.function.BiFunction;
+import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
@@ -402,4 +404,16 @@
         }
 
+        /**
+         * First applies {@code mapper} to both sides and then applies {@code operator} on the two results.
+         * @param mapper the mapping function
+         * @param operator the operator
+         * @param <T> the type of the intermediate result
+         * @param <U> the type of the result
+         * @return {@code operator.apply(mapper.apply(lhs), mapper.apply(rhs))}
+         */
+        public <T, U> U map(Function<Match, T> mapper, BiFunction<T, T, U> operator) {
+            return operator.apply(mapper.apply(lhs), mapper.apply(rhs));
+        }
+
         protected static String parenthesis(Match m) {
             return '(' + m.toString() + ')';
@@ -562,6 +576,5 @@
         @Override
         public String toString() {
-            return (lhs instanceof AbstractBinaryMatch && !(lhs instanceof And) ? parenthesis(lhs) : lhs) + " && "
-                 + (rhs instanceof AbstractBinaryMatch && !(rhs instanceof And) ? parenthesis(rhs) : rhs);
+            return map(m -> m instanceof AbstractBinaryMatch && !(m instanceof And) ? parenthesis(m) : m, (s1, s2) -> s1 + " && " + s2);
         }
     }
@@ -592,6 +605,5 @@
         @Override
         public String toString() {
-            return (lhs instanceof AbstractBinaryMatch && !(lhs instanceof Or) ? parenthesis(lhs) : lhs) + " || "
-                 + (rhs instanceof AbstractBinaryMatch && !(rhs instanceof Or) ? parenthesis(rhs) : rhs);
+            return map(m -> m instanceof AbstractBinaryMatch && !(m instanceof Or) ? parenthesis(m) : m, (s1, s2) -> s1 + " || " + s2);
         }
     }
@@ -622,6 +634,5 @@
         @Override
         public String toString() {
-            return (lhs instanceof AbstractBinaryMatch && !(lhs instanceof Xor) ? parenthesis(lhs) : lhs) + " ^ "
-                 + (rhs instanceof AbstractBinaryMatch && !(rhs instanceof Xor) ? parenthesis(rhs) : rhs);
+            return map(m -> m instanceof AbstractBinaryMatch && !(m instanceof Xor) ? parenthesis(m) : m, (s1, s2) -> s1 + " ^ " + s2);
         }
     }