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/compiler/frontend/src/org/jetbrains/jet/lang/cfg/JetFlowInformationProvider.java b/compiler/frontend/src/org/jetbrains/jet/lang/cfg/JetFlowInformationProvider.java
index 4f3446cab05..a23ea8dece9 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/cfg/JetFlowInformationProvider.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/cfg/JetFlowInformationProvider.java
@@ -556,10 +556,10 @@ public class JetFlowInformationProvider {
                     JetDeclaration element = ((VariableDeclarationInstruction) instruction).getVariableDeclarationElement();
                     if (element instanceof JetNamedDeclaration) {
                         PsiElement nameIdentifier = ((JetNamedDeclaration) element).getNameIdentifier();
-                        PsiElement elementToMark = nameIdentifier != null ? nameIdentifier : element;
+                        if (nameIdentifier == null) return;
                         if (variableStatus == null || variableStatus == VariableStatus.UNUSED) {
                             if (element instanceof JetProperty) {
-                                trace.report(Errors.UNUSED_VARIABLE.on((JetProperty) element, elementToMark, variableDescriptor));
+                                trace.report(Errors.UNUSED_VARIABLE.on((JetProperty) element, nameIdentifier, variableDescriptor));
                             }
                             else if (element instanceof JetParameter) {
                                 PsiElement psiElement = element.getParent().getParent();
@@ -569,13 +569,13 @@ public class JetFlowInformationProvider {
                                     assert descriptor instanceof FunctionDescriptor;
                                     FunctionDescriptor functionDescriptor = (FunctionDescriptor) descriptor;
                                     if (!isMain && !functionDescriptor.getModality().isOverridable() && functionDescriptor.getOverriddenDescriptors().isEmpty()) {
-                                        trace.report(Errors.UNUSED_PARAMETER.on((JetParameter) element, elementToMark, variableDescriptor));
+                                        trace.report(Errors.UNUSED_PARAMETER.on((JetParameter) element, nameIdentifier, variableDescriptor));
                                     }
                                 }
                             }
                         }
                         else if (variableStatus == VariableStatus.ONLY_WRITTEN && element instanceof JetProperty) {
-                            trace.report(Errors.ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE.on((JetNamedDeclaration) element, elementToMark, variableDescriptor));
+                            trace.report(Errors.ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE.on((JetNamedDeclaration) element, nameIdentifier, variableDescriptor));
                         }
                         else if (variableStatus == VariableStatus.WRITTEN && element instanceof JetProperty) {
                             JetExpression initializer = ((JetProperty) element).getInitializer();
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/DeclarationsChecker.java b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/DeclarationsChecker.java
index 9254fcdc0de..94ea67e824e 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/DeclarationsChecker.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/DeclarationsChecker.java
@@ -221,18 +221,17 @@ public class DeclarationsChecker {
         boolean backingFieldRequired = context.getTrace().getBindingContext().get(BindingContext.BACKING_FIELD_REQUIRED, propertyDescriptor);
 
         PsiElement nameIdentifier = property.getNameIdentifier();
-        ASTNode nameNode = nameIdentifier == null ? property.getNode() : nameIdentifier.getNode();
 
-        if (inTrait && backingFieldRequired && hasAccessorImplementation) {
-            context.getTrace().report(BACKING_FIELD_IN_TRAIT.on(nameNode));
+        if (inTrait && backingFieldRequired && hasAccessorImplementation && nameIdentifier != null) {
+            context.getTrace().report(BACKING_FIELD_IN_TRAIT.on(nameIdentifier));
         }
         if (initializer == null) {
-            if (backingFieldRequired && !inTrait && !context.getTrace().getBindingContext().get(BindingContext.IS_INITIALIZED, propertyDescriptor)) {
+            if (nameIdentifier != null && backingFieldRequired && !inTrait && !context.getTrace().getBindingContext().get(BindingContext.IS_INITIALIZED, propertyDescriptor)) {
                 if (classDescriptor == null || hasAccessorImplementation) {
-                    context.getTrace().report(MUST_BE_INITIALIZED.on(nameNode));
+                    context.getTrace().report(MUST_BE_INITIALIZED.on(nameIdentifier));
                 }
                 else {
-                    context.getTrace().report(MUST_BE_INITIALIZED_OR_BE_ABSTRACT.on(property, nameNode));
+                    context.getTrace().report(MUST_BE_INITIALIZED_OR_BE_ABSTRACT.on(property, nameIdentifier));
                 }
             }
             return;
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/OverrideResolver.java b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/OverrideResolver.java
index ccd0c4d9385..2c060f36b97 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/OverrideResolver.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/OverrideResolver.java
@@ -117,10 +117,10 @@ public class OverrideResolver {
         else if (klass instanceof JetObjectDeclaration) {
             nameIdentifier = ((JetObjectDeclaration) klass).getNameIdentifier();
         }
-        PsiElement elementToMark = nameIdentifier != null ? nameIdentifier : klass;
+        if (nameIdentifier == null) return;
 
         for (CallableMemberDescriptor memberDescriptor : manyImpl) {
-            context.getTrace().report(MANY_IMPL_MEMBER_NOT_IMPLEMENTED.on(elementToMark, klass, memberDescriptor));
+            context.getTrace().report(MANY_IMPL_MEMBER_NOT_IMPLEMENTED.on(nameIdentifier, klass, memberDescriptor));
             break;
         }
 
@@ -130,7 +130,7 @@ public class OverrideResolver {
         }
 
         for (CallableMemberDescriptor memberDescriptor : abstractNoImpl) {
-            context.getTrace().report(ABSTRACT_MEMBER_NOT_IMPLEMENTED.on(elementToMark, klass, memberDescriptor));
+            context.getTrace().report(ABSTRACT_MEMBER_NOT_IMPLEMENTED.on(nameIdentifier, klass, memberDescriptor));
             break;
         }
 
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/CallResolver.java b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/CallResolver.java
index 18524d28943..466b318ed58 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/CallResolver.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/CallResolver.java
@@ -19,6 +19,7 @@ import org.jetbrains.jet.lang.resolve.scopes.receivers.ReceiverDescriptor;
 import org.jetbrains.jet.lang.types.*;
 import org.jetbrains.jet.lang.types.expressions.ExpressionTypingServices;
 import org.jetbrains.jet.lang.types.expressions.OperatorConventions;
+import org.jetbrains.jet.lexer.JetToken;
 import org.jetbrains.jet.lexer.JetTokens;
 
 import java.util.*;
@@ -344,7 +345,7 @@ public class CallResolver {
                     if (callElement instanceof JetBinaryExpression) {
                         JetBinaryExpression binaryExpression = (JetBinaryExpression) callElement;
                         JetSimpleNameExpression operationReference = binaryExpression.getOperationReference();
-                        String operationString = operationReference.getReferencedNameElementType() == JetTokens.IDENTIFIER ? operationReference.getText() : OperatorConventions.getNameForOperationSymbol(operationReference.getReferencedNameElementType());
+                        String operationString = operationReference.getReferencedNameElementType() == JetTokens.IDENTIFIER ? operationReference.getText() : OperatorConventions.getNameForOperationSymbol((JetToken) operationReference.getReferencedNameElementType());
                         JetExpression right = binaryExpression.getRight();
                         if (right != null) {
                             trace.report(UNSAFE_INFIX_CALL.on(reference, binaryExpression.getLeft().getText(), operationString, right.getText()));
@@ -506,15 +507,6 @@ public class CallResolver {
                     }
                     else {
                         tracing.typeInferenceFailed(temporaryTrace, solution.getStatus());
-//                        // Substitute DONT_CARE types to make further type checking as tolerant as possible
-//                        D candidateWithDontCares = (D) candidate.substitute(TypeSubstitutor.makeConstantSubstitutor(candidate.getTypeParameters(), DONT_CARE));
-//                        if (candidateWithDontCares == null) {
-//                            candidateWithDontCares = (D) candidate.substitute(TypeSubstitutor.makeConstantSubstitutor(candidate.getTypeParameters(), Variance.INVARIANT, DONT_CARE));
-//                        }
-//                        if (!ErrorUtils.isErrorType(candidateWithDontCares.getReturnType())) {
-//                            // Returning an error type provokes overload resolution ambiguities that mask errors
-//                            candidateCall.setResultingDescriptor(candidateWithDontCares);
-//                        }
                         candidateCall.setStatus(OTHER_ERROR.combine(checkAllValueArguments(scope, tracing, task, candidateCall)));
                     }
                 }
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/OperatorConventions.java b/compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/OperatorConventions.java
index 570d75fb38b..2aea399ef4e 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/OperatorConventions.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/OperatorConventions.java
@@ -1,10 +1,11 @@
 package org.jetbrains.jet.lang.types.expressions;
 
+import com.google.common.collect.ImmutableBiMap;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
-import com.intellij.psi.tree.IElementType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.jet.lexer.JetToken;
 import org.jetbrains.jet.lexer.JetTokens;
 
 /**
@@ -12,6 +13,10 @@ import org.jetbrains.jet.lexer.JetTokens;
  */
 public class OperatorConventions {
 
+    public static final String EQUALS = "equals";
+    public static final String COMPARE_TO = "compareTo";
+    public static final String CONTAINS = "contains";
+
     private OperatorConventions() {}
 
     public static final ImmutableSet<String> NUMBER_CONVERSIONS = ImmutableSet.of(
@@ -23,7 +28,7 @@ public class OperatorConventions {
             "int"
     );
 
-    public static final ImmutableMap<IElementType, String> UNARY_OPERATION_NAMES = ImmutableMap.<IElementType, String>builder()
+    public static final ImmutableBiMap<JetToken, String> UNARY_OPERATION_NAMES = ImmutableBiMap.<JetToken, String>builder()
             .put(JetTokens.PLUSPLUS, "inc")
             .put(JetTokens.MINUSMINUS, "dec")
             .put(JetTokens.PLUS, "plus")
@@ -31,7 +36,7 @@ public class OperatorConventions {
             .put(JetTokens.EXCL, "not")
             .build();
 
-    public static final ImmutableMap<IElementType, String> BINARY_OPERATION_NAMES = ImmutableMap.<IElementType, String>builder()
+    public static final ImmutableBiMap<JetToken, String> BINARY_OPERATION_NAMES = ImmutableBiMap.<JetToken, String>builder()
             .put(JetTokens.MUL, "times")
             .put(JetTokens.PLUS, "plus")
             .put(JetTokens.MINUS, "minus")
@@ -41,11 +46,22 @@ public class OperatorConventions {
             .put(JetTokens.RANGE, "rangeTo")
             .build();
 
-    public static final ImmutableSet<IElementType> COMPARISON_OPERATIONS = ImmutableSet.<IElementType>of(JetTokens.LT, JetTokens.GT, JetTokens.LTEQ, JetTokens.GTEQ);
-    public static final ImmutableSet<IElementType> EQUALS_OPERATIONS = ImmutableSet.<IElementType>of(JetTokens.EQEQ, JetTokens.EXCLEQ);
+    public static final ImmutableSet<JetToken> NOT_OVERLOADABLE = 
+            ImmutableSet.<JetToken>of(JetTokens.ANDAND, JetTokens.OROR, JetTokens.ELVIS);
+    
+    public static final ImmutableSet<JetToken> INCREMENT_OPERATIONS =
+            ImmutableSet.<JetToken>of(JetTokens.PLUSPLUS, JetTokens.MINUSMINUS);
 
-    public static final ImmutableSet<IElementType> IN_OPERATIONS = ImmutableSet.<IElementType>of(JetTokens.IN_KEYWORD, JetTokens.NOT_IN);
-    public static final ImmutableMap<IElementType, String> ASSIGNMENT_OPERATIONS = ImmutableMap.<IElementType, String>builder()
+    public static final ImmutableSet<JetToken> COMPARISON_OPERATIONS =
+            ImmutableSet.<JetToken>of(JetTokens.LT, JetTokens.GT, JetTokens.LTEQ, JetTokens.GTEQ);
+
+    public static final ImmutableSet<JetToken> EQUALS_OPERATIONS =
+            ImmutableSet.<JetToken>of(JetTokens.EQEQ, JetTokens.EXCLEQ);
+
+    public static final ImmutableSet<JetToken> IN_OPERATIONS =
+            ImmutableSet.<JetToken>of(JetTokens.IN_KEYWORD, JetTokens.NOT_IN);
+
+    public static final ImmutableBiMap<JetToken, String> ASSIGNMENT_OPERATIONS = ImmutableBiMap.<JetToken, String>builder()
             .put(JetTokens.MULTEQ, "timesAssign")
             .put(JetTokens.DIVEQ, "divAssign")
             .put(JetTokens.PERCEQ, "modAssign")
@@ -53,7 +69,7 @@ public class OperatorConventions {
             .put(JetTokens.MINUSEQ, "minusAssign")
             .build();
 
-    public static final ImmutableMap<IElementType, IElementType> ASSIGNMENT_OPERATION_COUNTERPARTS = ImmutableMap.<IElementType, IElementType>builder()
+    public static final ImmutableMap<JetToken, JetToken> ASSIGNMENT_OPERATION_COUNTERPARTS = ImmutableMap.<JetToken, JetToken>builder()
             .put(JetTokens.MULTEQ, JetTokens.MUL)
             .put(JetTokens.DIVEQ, JetTokens.DIV)
             .put(JetTokens.PERCEQ, JetTokens.PERC)
@@ -62,17 +78,16 @@ public class OperatorConventions {
             .build();
     
     @Nullable
-    public static String getNameForOperationSymbol(@NotNull IElementType token) {
+    public static String getNameForOperationSymbol(@NotNull JetToken token) {
         String name = UNARY_OPERATION_NAMES.get(token);
         if (name != null) return name;
         name = BINARY_OPERATION_NAMES.get(token);
         if (name != null) return name;
         name = ASSIGNMENT_OPERATIONS.get(token);
         if (name != null) return name;
-        if (COMPARISON_OPERATIONS.contains(token)) return "compareTo";
-        if (EQUALS_OPERATIONS.contains(token)) return "equals";
-        if (IN_OPERATIONS.contains(token)) return "contains";
+        if (COMPARISON_OPERATIONS.contains(token)) return COMPARE_TO;
+        if (EQUALS_OPERATIONS.contains(token)) return EQUALS;
+        if (IN_OPERATIONS.contains(token)) return CONTAINS;
         return null;
-    } 
-
+    }
 }
diff --git a/compiler/testData/codegen/regressions/kt511.jet b/compiler/testData/codegen/regressions/kt511.jet
new file mode 100644
index 00000000000..a9bc915346c
--- /dev/null
+++ b/compiler/testData/codegen/regressions/kt511.jet
@@ -0,0 +1,16 @@
+namespace one_extends_base
+
+open class Base<T>(name : T?) {
+    var myName : T?
+    {
+        $myName = name
+    }
+}
+open class One<T, K>(name : T?, second : K?) : Base<T?>(name) {
+    var mySecond : K?
+    {
+        $mySecond = second
+    }
+}
+
+fun box() = if(One<String, Int>("ola", 0).myName == "ola") "OK" else "fail"
diff --git a/compiler/testData/codegen/regressions/kt779.jet b/compiler/testData/codegen/regressions/kt779.jet
new file mode 100644
index 00000000000..12aa290eb67
--- /dev/null
+++ b/compiler/testData/codegen/regressions/kt779.jet
@@ -0,0 +1,3 @@
+val <T> Array<T>.length : Int get() = this.size
+
+fun box() = if(Array(10, {1}).length == 10) "OK" else "fail"
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/controlFlowAnalysis/kt843.jet b/compiler/testData/diagnostics/tests/controlFlowAnalysis/kt843.jet
new file mode 100644
index 00000000000..3e276fe45d3
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/controlFlowAnalysis/kt843.jet
@@ -0,0 +1,8 @@
+//KT-843 Don't highlight incomplete variables as unused
+
+namespace kt843
+
+fun main(args : Array<String>) {
+    // Integer type
+    val // this word is grey, which looks strange
+<!SYNTAX!>}<!SYNTAX!><!><!>
\ No newline at end of file
diff --git a/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java b/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
index 5de65ac38f6..f14c34e279d 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/ArrayGenTest.java
@@ -12,6 +12,11 @@ public class ArrayGenTest extends CodegenTestCase {
 //        System.out.println(generateToText());
     }
 
+    public void testKt779 () throws Exception {
+        blackBoxFile("regressions/kt779.jet");
+//        System.out.println(generateToText());
+    }
+
     public void testCreateMultiInt () throws Exception {
         loadText("fun foo() = Array<Array<Int>> (5, { Array<Int>(it, {239}) })");
         Method foo = generateFunction();
diff --git a/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java b/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
index b2396c96af6..3949cf9b8c6 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/TypeInfoTest.java
@@ -138,6 +138,11 @@ public class TypeInfoTest extends CodegenTestCase {
 //        System.out.println(generateToText());
     }
 
+    public void testKt511() throws Exception {
+        blackBoxFile("regressions/kt511.jet");
+//        System.out.println(generateToText());
+    }
+
     public void testInner() throws Exception {
         blackBoxFile("typeInfo/inner.jet");
         System.out.println(generateToText());
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();
+}