diff --git a/compiler/frontend/src/jet/Library.jet b/compiler/frontend/src/jet/Library.jet
index 580d1dd1a2b..6feeeb7d334 100644
--- a/compiler/frontend/src/jet/Library.jet
+++ b/compiler/frontend/src/jet/Library.jet
@@ -103,6 +103,38 @@ trait Iterable<out T> {
   fun iterator() : Iterator<T>
 }
 
+trait ByteIterable : Iterable<Byte> {
+  override fun iterator() : ByteIterator
+}
+
+trait ShortIterable : Iterable<Short> {
+  override fun iterator() : ShortIterator
+}
+
+trait IntIterable : Iterable<Int> {
+  override fun iterator() : IntIterator
+}
+
+trait LongIterable : Iterable<Long> {
+  override fun iterator() : LongIterator
+}
+
+trait FloatIterable : Iterable<Float> {
+  override fun iterator() : FloatIterator
+}
+
+trait DoubleIterable : Iterable<Double> {
+  override fun iterator() : DoubleIterator
+}
+
+trait BooleanIterable : Iterable<Boolean> {
+  override fun iterator() : BooleanIterator
+}
+
+trait CharIterable : Iterable<Char> {
+  override fun iterator() : CharIterator
+}
+
 fun Array<T>(val size : Int) : Array<T?>
 
 class Array<T>(val size : Int, init : fun(Int) : T) {
@@ -230,7 +262,7 @@ trait Range<in T : Comparable<T>> {
   fun contains(item : T) : Boolean
 }
 
-class IntRange(val start : Int, size : Int, reversed : Boolean = false) : Range<Int>, Iterable<Int> {
+class IntRange(val start : Int, size : Int, reversed : Boolean = false) : Range<Int>, IntIterable {
     fun iterator () : Iterator<Int>
 
     fun contains (elem: Int) : Boolean
diff --git a/stdlib/src/jet/BooleanIterable.java b/stdlib/src/jet/BooleanIterable.java
new file mode 100644
index 00000000000..76d59748d65
--- /dev/null
+++ b/stdlib/src/jet/BooleanIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface BooleanIterable extends Iterable<Boolean> {
+    @Override
+    BooleanIterator iterator();
+}
diff --git a/stdlib/src/jet/ByteIterable.java b/stdlib/src/jet/ByteIterable.java
new file mode 100644
index 00000000000..36e773da574
--- /dev/null
+++ b/stdlib/src/jet/ByteIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface ByteIterable extends Iterable<Byte> {
+    @Override
+    ByteIterator iterator();
+}
diff --git a/stdlib/src/jet/CharIterable.java b/stdlib/src/jet/CharIterable.java
new file mode 100644
index 00000000000..d8646e449f3
--- /dev/null
+++ b/stdlib/src/jet/CharIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface CharIterable extends Iterable<Character> {
+    @Override
+    CharIterator iterator();
+}
diff --git a/stdlib/src/jet/DoubleIterable.java b/stdlib/src/jet/DoubleIterable.java
new file mode 100644
index 00000000000..ac6336039a2
--- /dev/null
+++ b/stdlib/src/jet/DoubleIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface DoubleIterable extends Iterable<Double> {
+    @Override
+    DoubleIterator iterator();
+}
diff --git a/stdlib/src/jet/FloatIterable.java b/stdlib/src/jet/FloatIterable.java
new file mode 100644
index 00000000000..5bbd25f3dd9
--- /dev/null
+++ b/stdlib/src/jet/FloatIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface FloatIterable extends Iterable<Float> {
+    @Override
+    FloatIterator iterator();
+}
diff --git a/stdlib/src/jet/IntIterable.java b/stdlib/src/jet/IntIterable.java
new file mode 100644
index 00000000000..0963ba1f099
--- /dev/null
+++ b/stdlib/src/jet/IntIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface IntIterable extends Iterable<Integer> {
+    @Override
+    IntIterator iterator();
+}
diff --git a/stdlib/src/jet/IntRange.java b/stdlib/src/jet/IntRange.java
index 13811dbba40..7866919f9fe 100644
--- a/stdlib/src/jet/IntRange.java
+++ b/stdlib/src/jet/IntRange.java
@@ -2,7 +2,7 @@ package jet;
 
 import jet.typeinfo.TypeInfo;
 
-public final class IntRange implements Range<Integer>, Iterable<Integer>, JetObject {
+public final class IntRange implements Range<Integer>, IntIterable, JetObject {
     private final static TypeInfo typeInfo = TypeInfo.getTypeInfo(IntRange.class, false);
 
     private final int start;
@@ -39,7 +39,7 @@ public final class IntRange implements Range<Integer>, Iterable<Integer>, JetObj
     }
 
     @Override
-    public Iterator<Integer> iterator() {
+    public IntIterator iterator() {
         return new MyIterator(start, count);
     }
 
@@ -66,7 +66,7 @@ public final class IntRange implements Range<Integer>, Iterable<Integer>, JetObj
         }
     }
 
-    private static class MyIterator implements Iterator<Integer> {
+    private static class MyIterator extends IntIterator {
         private final static TypeInfo typeInfo = TypeInfo.getTypeInfo(MyIterator.class, false);
 
         private int cur;
@@ -86,7 +86,7 @@ public final class IntRange implements Range<Integer>, Iterable<Integer>, JetObj
         }
 
         @Override
-        public Integer next() {
+        public int nextInt() {
             count--;
             if(reversed) {
                 return cur--;
diff --git a/stdlib/src/jet/LongIterable.java b/stdlib/src/jet/LongIterable.java
new file mode 100644
index 00000000000..79567c0604b
--- /dev/null
+++ b/stdlib/src/jet/LongIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface LongIterable extends Iterable<Long> {
+    @Override
+    LongIterator iterator();
+}
diff --git a/stdlib/src/jet/LongRange.java b/stdlib/src/jet/LongRange.java
index ed94c76cb31..dea5c70402e 100644
--- a/stdlib/src/jet/LongRange.java
+++ b/stdlib/src/jet/LongRange.java
@@ -2,7 +2,7 @@ package jet;
 
 import jet.typeinfo.TypeInfo;
 
-public final class LongRange implements Range<Long>, Iterable<Long>, JetObject {
+public final class LongRange implements Range<Long>, LongIterable, JetObject {
     private final static TypeInfo typeInfo = TypeInfo.getTypeInfo(IntRange.class, false);
 
     private final long start;
@@ -39,7 +39,7 @@ public final class LongRange implements Range<Long>, Iterable<Long>, JetObject {
     }
 
     @Override
-    public Iterator<Long> iterator() {
+    public LongIterator iterator() {
         return new MyIterator(start, count);
     }
 
@@ -66,7 +66,7 @@ public final class LongRange implements Range<Long>, Iterable<Long>, JetObject {
         }
     }
 
-    private static class MyIterator implements Iterator<Long> {
+    private static class MyIterator extends LongIterator {
         private final static TypeInfo typeInfo = TypeInfo.getTypeInfo(MyIterator.class, false);
 
         private long cur;
@@ -86,7 +86,7 @@ public final class LongRange implements Range<Long>, Iterable<Long>, JetObject {
         }
 
         @Override
-        public Long next() {
+        public long nextLong() {
             count--;
             if(reversed) {
                 return cur--;
diff --git a/stdlib/src/jet/ShortIterable.java b/stdlib/src/jet/ShortIterable.java
new file mode 100644
index 00000000000..9da1721794b
--- /dev/null
+++ b/stdlib/src/jet/ShortIterable.java
@@ -0,0 +1,9 @@
+package jet;
+
+/**
+ * @author alex.tkachman
+ */
+public interface ShortIterable extends Iterable<Short> {
+    @Override
+    ShortIterator iterator();
+}