diff --git a/platform/platform-api/src/com/intellij/lexer/LookAheadLexer.java b/platform/platform-api/src/com/intellij/lexer/LookAheadLexer.java
index b388f6892c28..17c9bd6294d0 100644
--- a/platform/platform-api/src/com/intellij/lexer/LookAheadLexer.java
+++ b/platform/platform-api/src/com/intellij/lexer/LookAheadLexer.java
@@ -92,6 +92,10 @@ public abstract class LookAheadLexer extends LexerBase{
     }
   }
 
+  public IElementType replaceCachedType(int index, IElementType token) {
+    return myTypeCache.set(index, token);
+  }
+
   public int getState() {
     int offset = myTokenStart - myLastOffset;
     return myLastState | (offset << 16);
diff --git a/platform/util/src/com/intellij/util/containers/Queue.java b/platform/util/src/com/intellij/util/containers/Queue.java
index 0e2e81495ada..cf73a493e961 100644
--- a/platform/util/src/com/intellij/util/containers/Queue.java
+++ b/platform/util/src/com/intellij/util/containers/Queue.java
@@ -121,6 +121,23 @@ public class Queue<T> {
     isWrapped = false;
   }
 
+  public T set(int index, T value) {
+    int arrayIndex;
+    if (isWrapped) {
+      if (myFirst + index >= myArray.length) {
+        arrayIndex = index - myArray.length + myFirst;
+      }
+      else
+        arrayIndex = myFirst + index;
+    }
+    else {
+      arrayIndex = myFirst + index;
+    }
+    final Object old = myArray[arrayIndex];
+    myArray[arrayIndex] = value;
+    return (T)old;
+  }
+
   public boolean process(@NotNull Processor<T> processor) {
     if (isWrapped) {
       for (int i = myFirst; i < myArray.length; i++) {
diff --git a/platform/util/testSrc/com/intellij/util/containers/QueueTest.java b/platform/util/testSrc/com/intellij/util/containers/QueueTest.java
index aa9879ddee4d..98599b66978e 100644
--- a/platform/util/testSrc/com/intellij/util/containers/QueueTest.java
+++ b/platform/util/testSrc/com/intellij/util/containers/QueueTest.java
@@ -78,6 +78,29 @@ public class QueueTest extends TestCase {
     }
   }
 
+  public void testSetting() {
+    com.intellij.util.containers.Queue queue = new com.intellij.util.containers.Queue(10);
+    for (int i = 0; i < 9; i++) {
+      queue.addLast(String.valueOf(i));
+    }
+    for (int i = 0; i < 4; i++) {
+      Object first = queue.pullFirst();
+      queue.addLast(first);
+    }
+
+    Assert.assertEquals(String.valueOf(4), queue.peekFirst());
+    for (int i = 0; i < 5; i++) {
+      Assert.assertEquals(String.valueOf(i + 4), queue.set(i, String.valueOf(i*i)));
+    }
+    for (int i = 0; i < 4; i++) {
+      int k = i + 5;
+      Assert.assertEquals(String.valueOf(i), queue.set(k, String.valueOf(k*k)));
+    }
+    for (int i = 0; i < 9; i++) {
+      Assert.assertEquals(String.valueOf(i*i), queue.pullFirst());
+    }
+  }
+
 
   public void testCycling() {
     com.intellij.util.containers.Queue queue = new com.intellij.util.containers.Queue(10);