Index: src/OFSet.h
==================================================================
--- src/OFSet.h
+++ src/OFSet.h
@@ -23,11 +23,12 @@
 @class OFArray;
 
 /**
  * \brief An unordered set of unique objects.
  */
-@interface OFSet: OFObject <OFCollection, OFCopying, OFMutableCopying>
+@interface OFSet: OFObject <OFCollection, OFCopying, OFMutableCopying,
+    OFFastEnumeration>
 {
 	OFMutableDictionary *dictionary;
 }
 
 /**

Index: src/OFSet.m
==================================================================
--- src/OFSet.m
+++ src/OFSet.m
@@ -266,6 +266,45 @@
 
 - (OFEnumerator*)objectEnumerator
 {
 	return [dictionary keyEnumerator];
 }
+
+- (int)countByEnumeratingWithState: (of_fast_enumeration_state_t*)state
+			   objects: (id*)objects
+			     count: (int)count
+{
+	OFAutoreleasePool *pool = state->extra.pointers[0];
+	OFEnumerator *enumerator = state->extra.pointers[1];
+	int i;
+
+	state->itemsPtr = objects;
+	state->mutationsPtr = (unsigned long*)self;
+
+	if (state->state == -1)
+		return 0;
+
+	if (state->state == 0) {
+		pool = [[OFAutoreleasePool alloc] init];
+		enumerator = [dictionary keyEnumerator];
+
+		state->extra.pointers[0] = pool;
+		state->extra.pointers[1] = enumerator;
+
+		state->state = 1;
+	}
+
+	for (i = 0; i < count; i++) {
+		id object = [enumerator nextObject];
+
+		if (object == nil) {
+			[pool release];
+			state->state = -1;
+			return i;
+		}
+
+		objects[i] = object;
+	}
+
+	return count;
+}
 @end

Index: tests/OFSet.m
==================================================================
--- tests/OFSet.m
+++ tests/OFSet.m
@@ -28,10 +28,14 @@
 - (void)setTests
 {
 	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
 	OFSet *set1, *set2;
 	OFMutableSet *mutableSet;
+#ifdef OF_HAVE_FAST_ENUMERATION
+	BOOL ok;
+	size_t i;
+#endif
 
 	TEST(@"+[setWithArray:]",
 	    (set1 = [OFSet setWithArray: [OFArray arrayWithObjects: @"foo",
 	    @"bar", @"baz", @"foo", @"x", nil]]))
 
@@ -68,9 +72,42 @@
 
 	TEST(@"-[intersectsSet:]",
 	    [(set2 = [OFSet setWithObjects: @"x", nil]) intersectsSet: set1] &&
 	    [set1 intersectsSet: set2] &&
 	    ![([OFSet setWithObjects: @"1", nil]) intersectsSet: set1]);
+
+#ifdef OF_HAVE_FAST_ENUMERATION
+	ok = YES;
+	i = 0;
+
+	for (OFString *s in set1) {
+		switch (i) {
+		case 0:
+			if (![s isEqual: @"bar"])
+				ok = NO;
+			break;
+		case 1:
+			if (![s isEqual: @"baz"])
+				ok = NO;
+			break;
+		case 2:
+			if (![s isEqual: @"foo"])
+				ok = NO;
+			break;
+		case 3:
+			if (![s isEqual: @"x"])
+				ok = NO;
+			break;
+		}
+
+		i++;
+	}
+
+	if (i != 4)
+		ok = NO;
+
+	TEST(@"Fast enumeration", ok)
+#endif
 
 	[pool drain];
 }
 @end