diff --git a/compiler/frontend/src/jet/Ranges.jet b/compiler/frontend/src/jet/Ranges.jet
index d8cc3edb9d6..0838f01df81 100644
--- a/compiler/frontend/src/jet/Ranges.jet
+++ b/compiler/frontend/src/jet/Ranges.jet
@@ -6,71 +6,85 @@ public trait Range<in T : Comparable<T>> {
     public fun contains(item : T) : Boolean
 }
 
-public class IntRange(public override val start : Int, public override val end : Int) : Range<Int>, IntIterable {
+public class IntRange(public override val start : Int, public override val end : Int) : Range<Int>, NumberSequence<Int>, IntIterable {
     public override fun iterator () : IntIterator
 
     public override fun contains (elem: Int) : Boolean
 
+    public override val increment: Int
+
     public class object {
         public val EMPTY: IntRange
     }
 }
 
-public class LongRange(public override val start : Long, public override val end : Long) : Range<Long>, LongIterable {
+public class LongRange(public override val start : Long, public override val end : Long) : Range<Long>, NumberSequence<Long>, LongIterable {
     public override fun iterator () : LongIterator
 
     public override fun contains (elem: Long) : Boolean
 
+    public override val increment: Long
+
     public class object {
         public val EMPTY: LongRange
     }
 }
 
-public class ByteRange(public override val start : Byte, public override val end : Byte) : Range<Byte>, ByteIterable {
+public class ByteRange(public override val start : Byte, public override val end : Byte) : Range<Byte>, NumberSequence<Byte>, ByteIterable {
     public override fun iterator () : ByteIterator
 
     public override fun contains (elem: Byte) : Boolean
 
+    public override val increment: Int
+
     public class object {
         public val EMPTY: ByteRange
     }
 }
 
-public class ShortRange(public override val start : Short, public override val end : Short) : Range<Short>, ShortIterable {
+public class ShortRange(public override val start : Short, public override val end : Short) : Range<Short>, NumberSequence<Short>, ShortIterable {
     public override fun iterator () : ShortIterator
 
     public override fun contains (elem: Short) : Boolean
 
+    public override val increment: Int
+
     public class object {
         public val EMPTY: ShortRange
     }
 }
 
-public class CharRange(public override val start : Char, public override val end : Char) : Range<Char>, CharIterable {
+public class CharRange(public override val start : Char, public override val end : Char) : Range<Char>, NumberSequence<Char>, CharIterable {
     public override fun iterator () : CharIterator
 
     public override fun contains (elem: Char) : Boolean
 
+    public override val increment: Int
+
     public class object {
         public val EMPTY: CharRange
     }
 }
 
-public class FloatRange(public override val start : Float, public override val end : Float) : Range<Float>, FloatIterable {
+public class FloatRange(public override val start : Float, public override val end : Float) : Range<Float>, NumberSequence<Float>, FloatIterable {
     public override fun iterator () : FloatIterator
 
     public override fun contains (elem: Float) : Boolean
 
+    public override val increment: Float
+
     public class object {
         public val EMPTY: FloatRange
     }
 }
 
-public class DoubleRange(public override val start : Double, public override val end : Double) : Range<Double>, DoubleIterable {
+public class DoubleRange(public override val start : Double, public override val end : Double) : Range<Double>, NumberSequence<Double>, DoubleIterable {
     public override fun iterator () : DoubleIterator
 
     public override fun contains (elem: Double) : Boolean
 
+    public override val increment: Double
+
     public class object {
         public val EMPTY: DoubleRange
     }
diff --git a/runtime/src/jet/ByteRange.java b/runtime/src/jet/ByteRange.java
index 6b75f0fb143..95307785dbb 100644
--- a/runtime/src/jet/ByteRange.java
+++ b/runtime/src/jet/ByteRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class ByteRange implements Range<Byte>, ByteIterable {
+public final class ByteRange implements Range<Byte>, NumberSequence<Byte>, ByteIterable {
     private final byte start;
     private final byte end;
 
@@ -74,6 +74,11 @@ public final class ByteRange implements Range<Byte>, ByteIterable {
         return end;
     }
 
+    @Override
+    public Integer getIncrement() {
+        return 1;
+    }
+
     @Override
     public ByteIterator iterator() {
         return new ByteSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/CharRange.java b/runtime/src/jet/CharRange.java
index e92f1f760df..d288b29ef39 100644
--- a/runtime/src/jet/CharRange.java
+++ b/runtime/src/jet/CharRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class CharRange implements Range<Character>, CharIterable {
+public final class CharRange implements Range<Character>, NumberSequence<Character>, CharIterable {
     private final char start;
     private final char end;
 
@@ -74,6 +74,11 @@ public final class CharRange implements Range<Character>, CharIterable {
         return end;
     }
 
+    @Override
+    public Integer getIncrement() {
+        return 1;
+    }
+
     @Override
     public CharIterator iterator() {
         return new CharacterSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/DoubleRange.java b/runtime/src/jet/DoubleRange.java
index 9dcbe36a843..98c53c889ae 100644
--- a/runtime/src/jet/DoubleRange.java
+++ b/runtime/src/jet/DoubleRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class DoubleRange implements Range<Double>, DoubleIterable {
+public final class DoubleRange implements Range<Double>, NumberSequence<Double>, DoubleIterable {
     private final double start;
     private final double end;
 
@@ -75,6 +75,11 @@ public final class DoubleRange implements Range<Double>, DoubleIterable {
         return end;
     }
 
+    @Override
+    public Double getIncrement() {
+        return 1.0;
+    }
+
     @Override
     public DoubleIterator iterator() {
         return new DoubleSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/FloatRange.java b/runtime/src/jet/FloatRange.java
index 418bfe256a1..08decd965fd 100644
--- a/runtime/src/jet/FloatRange.java
+++ b/runtime/src/jet/FloatRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class FloatRange implements Range<Float>, FloatIterable {
+public final class FloatRange implements Range<Float>, NumberSequence<Float>, FloatIterable {
     private final float start;
     private final float end;
 
@@ -71,6 +71,11 @@ public final class FloatRange implements Range<Float>, FloatIterable {
         return end;
     }
 
+    @Override
+    public Float getIncrement() {
+        return 1.0f;
+    }
+
     @Override
     public FloatIterator iterator() {
         return new FloatSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/IntRange.java b/runtime/src/jet/IntRange.java
index dd4c9470e67..2d26265ebaa 100644
--- a/runtime/src/jet/IntRange.java
+++ b/runtime/src/jet/IntRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class IntRange implements Range<Integer>, IntIterable {
+public final class IntRange implements Range<Integer>, NumberSequence<Integer>, IntIterable {
     private final int start;
     private final int end;
 
@@ -74,6 +74,11 @@ public final class IntRange implements Range<Integer>, IntIterable {
         return end;
     }
 
+    @Override
+    public Integer getIncrement() {
+        return 1;
+    }
+
     @Override
     public IntIterator iterator() {
         return new IntSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/LongRange.java b/runtime/src/jet/LongRange.java
index d52e048c513..4cc57c2679f 100644
--- a/runtime/src/jet/LongRange.java
+++ b/runtime/src/jet/LongRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class LongRange implements Range<Long>, LongIterable {
+public final class LongRange implements Range<Long>, NumberSequence<Long>, LongIterable {
     private final long start;
     private final long end;
 
@@ -74,6 +74,11 @@ public final class LongRange implements Range<Long>, LongIterable {
         return end;
     }
 
+    @Override
+    public Long getIncrement() {
+        return 1L;
+    }
+
     @Override
     public LongIterator iterator() {
         return new LongSequenceIterator(getStart(), getEnd(), 1);
diff --git a/runtime/src/jet/ShortRange.java b/runtime/src/jet/ShortRange.java
index e634f70665a..f6370865dcf 100644
--- a/runtime/src/jet/ShortRange.java
+++ b/runtime/src/jet/ShortRange.java
@@ -19,7 +19,7 @@ package jet;
 import org.jetbrains.jet.rt.annotation.AssertInvisibleInResolver;
 
 @AssertInvisibleInResolver
-public final class ShortRange implements Range<Short>, ShortIterable {
+public final class ShortRange implements Range<Short>, NumberSequence<Short>, ShortIterable {
     private final short start;
     private final short end;
 
@@ -74,6 +74,11 @@ public final class ShortRange implements Range<Short>, ShortIterable {
         return end;
     }
 
+    @Override
+    public Integer getIncrement() {
+        return 1;
+    }
+
     @Override
     public ShortIterator iterator() {
         return new ShortSequenceIterator(getStart(), getEnd(), 1);