From 1361c70f681fac743f4ad978096d111768ba3494 Mon Sep 17 00:00:00 2001
From: Andrey Breslav <andrey.breslav@jetbrains.com>
Date: Tue, 26 Jun 2012 19:47:53 +0200
Subject: [PATCH] FunctionN and ExtensionFunctionN are now abstract classes,
 not traits

+ Indexing of their type parameters is fixed (should match actual positions in the parameter list)

 The reason to make them classes:
 * This is how they are actually implemented in the JVM back-end (for performance)

 This can be reconsidered later, but seems to be a reasonable solution
---
 .../TuplesAndFunctionsGenerator.java          |  4 +-
 .../src/jet.src/ExtensionFunctions.jet        | 92 +++++++++----------
 compiler/frontend/src/jet.src/Functions.jet   | 92 +++++++++----------
 .../descriptors/FunctionDescriptorImpl.java   |  5 +-
 .../lang/types/lang/JetStandardClasses.java   | 31 +++++--
 5 files changed, 118 insertions(+), 106 deletions(-)

diff --git a/compiler/frontend/generator/TuplesAndFunctionsGenerator.java b/compiler/frontend/generator/TuplesAndFunctionsGenerator.java
index c650b0092c5..cd3b55a913e 100644
--- a/compiler/frontend/generator/TuplesAndFunctionsGenerator.java
+++ b/compiler/frontend/generator/TuplesAndFunctionsGenerator.java
@@ -52,7 +52,7 @@ public class TuplesAndFunctionsGenerator {
     private static void generateFunctions(PrintStream out, int count, boolean extension) {
         generated(out);
         for (int i = 0; i < count; i++) {
-            out.print("public trait " + (extension ? "ExtensionFunction" : "Function") + i);
+            out.print("public abstract class " + (extension ? "ExtensionFunction" : "Function") + i);
             out.print("<");
             if (extension) {
                 out.print("in T");
@@ -65,7 +65,7 @@ public class TuplesAndFunctionsGenerator {
                 out.print(", ");
             }
             out.print("out R> {\n");
-            out.print("  public fun " + (extension ? "T." : "") +
+            out.print("  public abstract fun " + (extension ? "T." : "") +
                       "invoke(");
             for (int j = 1; j <= i; j++) {
                 out.print("p" + j + ": " + "P" + j);
diff --git a/compiler/frontend/src/jet.src/ExtensionFunctions.jet b/compiler/frontend/src/jet.src/ExtensionFunctions.jet
index a3d2954fb45..caadfe24762 100644
--- a/compiler/frontend/src/jet.src/ExtensionFunctions.jet
+++ b/compiler/frontend/src/jet.src/ExtensionFunctions.jet
@@ -3,72 +3,72 @@
 
 package jet
 
-public trait ExtensionFunction0<in T, out R> {
-  public fun T.invoke() : R
+public abstract class ExtensionFunction0<in T, out R> {
+  public abstract fun T.invoke() : R
 }
-public trait ExtensionFunction1<in T, in P1, out R> {
-  public fun T.invoke(p1: P1) : R
+public abstract class ExtensionFunction1<in T, in P1, out R> {
+  public abstract fun T.invoke(p1: P1) : R
 }
-public trait ExtensionFunction2<in T, in P1, in P2, out R> {
-  public fun T.invoke(p1: P1, p2: P2) : R
+public abstract class ExtensionFunction2<in T, in P1, in P2, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2) : R
 }
-public trait ExtensionFunction3<in T, in P1, in P2, in P3, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3) : R
+public abstract class ExtensionFunction3<in T, in P1, in P2, in P3, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3) : R
 }
-public trait ExtensionFunction4<in T, in P1, in P2, in P3, in P4, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4) : R
+public abstract class ExtensionFunction4<in T, in P1, in P2, in P3, in P4, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4) : R
 }
-public trait ExtensionFunction5<in T, in P1, in P2, in P3, in P4, in P5, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5) : R
+public abstract class ExtensionFunction5<in T, in P1, in P2, in P3, in P4, in P5, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5) : R
 }
-public trait ExtensionFunction6<in T, in P1, in P2, in P3, in P4, in P5, in P6, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6) : R
+public abstract class ExtensionFunction6<in T, in P1, in P2, in P3, in P4, in P5, in P6, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6) : R
 }
-public trait ExtensionFunction7<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7) : R
+public abstract class ExtensionFunction7<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7) : R
 }
-public trait ExtensionFunction8<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8) : R
+public abstract class ExtensionFunction8<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8) : R
 }
-public trait ExtensionFunction9<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9) : R
+public abstract class ExtensionFunction9<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9) : R
 }
-public trait ExtensionFunction10<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10) : R
+public abstract class ExtensionFunction10<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10) : R
 }
-public trait ExtensionFunction11<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11) : R
+public abstract class ExtensionFunction11<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11) : R
 }
-public trait ExtensionFunction12<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12) : R
+public abstract class ExtensionFunction12<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12) : R
 }
-public trait ExtensionFunction13<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13) : R
+public abstract class ExtensionFunction13<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13) : R
 }
-public trait ExtensionFunction14<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14) : R
+public abstract class ExtensionFunction14<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14) : R
 }
-public trait ExtensionFunction15<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15) : R
+public abstract class ExtensionFunction15<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15) : R
 }
-public trait ExtensionFunction16<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16) : R
+public abstract class ExtensionFunction16<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16) : R
 }
-public trait ExtensionFunction17<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17) : R
+public abstract class ExtensionFunction17<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17) : R
 }
-public trait ExtensionFunction18<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18) : R
+public abstract class ExtensionFunction18<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18) : R
 }
-public trait ExtensionFunction19<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19) : R
+public abstract class ExtensionFunction19<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19) : R
 }
-public trait ExtensionFunction20<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20) : R
+public abstract class ExtensionFunction20<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20) : R
 }
-public trait ExtensionFunction21<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21) : R
+public abstract class ExtensionFunction21<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21) : R
 }
-public trait ExtensionFunction22<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, in P22, out R> {
-  public fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21, p22: P22) : R
+public abstract class ExtensionFunction22<in T, in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, in P22, out R> {
+  public abstract fun T.invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21, p22: P22) : R
 }
diff --git a/compiler/frontend/src/jet.src/Functions.jet b/compiler/frontend/src/jet.src/Functions.jet
index f0e0d901d03..b272697bceb 100644
--- a/compiler/frontend/src/jet.src/Functions.jet
+++ b/compiler/frontend/src/jet.src/Functions.jet
@@ -3,72 +3,72 @@
 
 package jet
 
-public trait Function0<out R> {
-  public fun invoke() : R
+public abstract class Function0<out R> {
+  public abstract fun invoke() : R
 }
-public trait Function1<in P1, out R> {
-  public fun invoke(p1: P1) : R
+public abstract class Function1<in P1, out R> {
+  public abstract fun invoke(p1: P1) : R
 }
-public trait Function2<in P1, in P2, out R> {
-  public fun invoke(p1: P1, p2: P2) : R
+public abstract class Function2<in P1, in P2, out R> {
+  public abstract fun invoke(p1: P1, p2: P2) : R
 }
-public trait Function3<in P1, in P2, in P3, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3) : R
+public abstract class Function3<in P1, in P2, in P3, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3) : R
 }
-public trait Function4<in P1, in P2, in P3, in P4, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4) : R
+public abstract class Function4<in P1, in P2, in P3, in P4, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4) : R
 }
-public trait Function5<in P1, in P2, in P3, in P4, in P5, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5) : R
+public abstract class Function5<in P1, in P2, in P3, in P4, in P5, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5) : R
 }
-public trait Function6<in P1, in P2, in P3, in P4, in P5, in P6, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6) : R
+public abstract class Function6<in P1, in P2, in P3, in P4, in P5, in P6, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6) : R
 }
-public trait Function7<in P1, in P2, in P3, in P4, in P5, in P6, in P7, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7) : R
+public abstract class Function7<in P1, in P2, in P3, in P4, in P5, in P6, in P7, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7) : R
 }
-public trait Function8<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8) : R
+public abstract class Function8<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8) : R
 }
-public trait Function9<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9) : R
+public abstract class Function9<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9) : R
 }
-public trait Function10<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10) : R
+public abstract class Function10<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10) : R
 }
-public trait Function11<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11) : R
+public abstract class Function11<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11) : R
 }
-public trait Function12<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12) : R
+public abstract class Function12<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12) : R
 }
-public trait Function13<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13) : R
+public abstract class Function13<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13) : R
 }
-public trait Function14<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14) : R
+public abstract class Function14<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14) : R
 }
-public trait Function15<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15) : R
+public abstract class Function15<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15) : R
 }
-public trait Function16<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16) : R
+public abstract class Function16<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16) : R
 }
-public trait Function17<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17) : R
+public abstract class Function17<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17) : R
 }
-public trait Function18<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18) : R
+public abstract class Function18<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18) : R
 }
-public trait Function19<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19) : R
+public abstract class Function19<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19) : R
 }
-public trait Function20<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20) : R
+public abstract class Function20<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20) : R
 }
-public trait Function21<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21) : R
+public abstract class Function21<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21) : R
 }
-public trait Function22<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, in P22, out R> {
-  public fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21, p22: P22) : R
+public abstract class Function22<in P1, in P2, in P3, in P4, in P5, in P6, in P7, in P8, in P9, in P10, in P11, in P12, in P13, in P14, in P15, in P16, in P17, in P18, in P19, in P20, in P21, in P22, out R> {
+  public abstract fun invoke(p1: P1, p2: P2, p3: P3, p4: P4, p5: P5, p6: P6, p7: P7, p8: P8, p9: P9, p10: P10, p11: P11, p12: P12, p13: P13, p14: P14, p15: P15, p16: P16, p17: P17, p18: P18, p19: P19, p20: P20, p21: P21, p22: P22) : R
 }
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/descriptors/FunctionDescriptorImpl.java b/compiler/frontend/src/org/jetbrains/jet/lang/descriptors/FunctionDescriptorImpl.java
index a342dce8bcb..9feb7d33985 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/descriptors/FunctionDescriptorImpl.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/descriptors/FunctionDescriptorImpl.java
@@ -91,8 +91,9 @@ public abstract class FunctionDescriptorImpl extends DeclarationDescriptorNonRoo
         this.expectedThisObject = expectedThisObject;
         
         for (int i = 0; i < typeParameters.size(); ++i) {
-            if (typeParameters.get(i).getIndex() != i) {
-                throw new IllegalStateException();
+            TypeParameterDescriptor typeParameterDescriptor = typeParameters.get(i);
+            if (typeParameterDescriptor.getIndex() != i) {
+                throw new IllegalStateException(typeParameterDescriptor + " index is " + typeParameterDescriptor.getIndex() + " but position is " + i);
             }
         }
 
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/types/lang/JetStandardClasses.java b/compiler/frontend/src/org/jetbrains/jet/lang/types/lang/JetStandardClasses.java
index 8d057b08481..d34a3bb326b 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/types/lang/JetStandardClasses.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/types/lang/JetStandardClasses.java
@@ -208,37 +208,48 @@ public class JetStandardClasses {
             ClassDescriptorImpl function = new ClassDescriptorImpl(
                     STANDARD_CLASSES_NAMESPACE,
                     Collections.<AnnotationDescriptor>emptyList(),
-                    Modality.OPEN,
+                    Modality.ABSTRACT,
                     Name.identifier("Function" + i));
 
             SimpleFunctionDescriptorImpl invoke = new SimpleFunctionDescriptorImpl(function, Collections.<AnnotationDescriptor>emptyList(), Name.identifier("invoke"), CallableMemberDescriptor.Kind.DECLARATION);
             WritableScope scopeForInvoke = createScopeForInvokeFunction(function, invoke);
-            List<TypeParameterDescriptor> typeParameters = createTypeParameters(i, function);
+            List<TypeParameterDescriptor> typeParameters = createTypeParameters(0, i, function);
+            ConstructorDescriptorImpl constructorDescriptorForFunction = new ConstructorDescriptorImpl(function, Collections.<AnnotationDescriptor>emptyList(), true);
             FUNCTION[i] = function.initialize(
                     false,
                     typeParameters,
-                    Collections.singleton(getAnyType()), scopeForInvoke, Collections.<ConstructorDescriptor>emptySet(), null);
+                    Collections.singleton(getAnyType()), scopeForInvoke, Collections.<ConstructorDescriptor>singleton(constructorDescriptorForFunction), null);
             FUNCTION_TYPE_CONSTRUCTORS.add(FUNCTION[i].getTypeConstructor());
             FunctionDescriptorUtil.initializeFromFunctionType(invoke, function.getDefaultType(), new ClassReceiver(FUNCTION[i]), Modality.ABSTRACT, Visibilities.PUBLIC);
 
+            constructorDescriptorForFunction.initialize(function.getTypeConstructor().getParameters(),
+                                             Collections.<ValueParameterDescriptor>emptyList(), Visibilities.PUBLIC);
+            constructorDescriptorForFunction.setReturnType(function.getDefaultType());
+
             ClassDescriptorImpl receiverFunction = new ClassDescriptorImpl(
                     STANDARD_CLASSES_NAMESPACE,
                     Collections.<AnnotationDescriptor>emptyList(),
-                    Modality.OPEN,
+                    Modality.ABSTRACT,
                     Name.identifier("ExtensionFunction" + i));
             SimpleFunctionDescriptorImpl invokeWithReceiver = new SimpleFunctionDescriptorImpl(receiverFunction, Collections.<AnnotationDescriptor>emptyList(), Name.identifier("invoke"), CallableMemberDescriptor.Kind.DECLARATION);
             WritableScope scopeForInvokeWithReceiver = createScopeForInvokeFunction(receiverFunction, invokeWithReceiver);
-            List<TypeParameterDescriptor> parameters = createTypeParameters(i, receiverFunction);
+            List<TypeParameterDescriptor> parameters = createTypeParameters(1, i, receiverFunction);
             parameters.add(0, TypeParameterDescriptorImpl.createWithDefaultBound(
                     receiverFunction,
                     Collections.<AnnotationDescriptor>emptyList(),
                     false, Variance.IN_VARIANCE, Name.identifier("T"), 0));
+
+            ConstructorDescriptorImpl constructorDescriptorForReceiverFunction = new ConstructorDescriptorImpl(function, Collections.<AnnotationDescriptor>emptyList(), true);
             RECEIVER_FUNCTION[i] = receiverFunction.initialize(
                     false,
                     parameters,
-                    Collections.singleton(getAnyType()), scopeForInvokeWithReceiver, Collections.<ConstructorDescriptor>emptySet(), null);
+                    Collections.singleton(getAnyType()), scopeForInvokeWithReceiver, Collections.<ConstructorDescriptor>singleton(constructorDescriptorForReceiverFunction), null);
             RECEIVER_FUNCTION_TYPE_CONSTRUCTORS.add(RECEIVER_FUNCTION[i].getTypeConstructor());
             FunctionDescriptorUtil.initializeFromFunctionType(invokeWithReceiver, receiverFunction.getDefaultType(), new ClassReceiver(RECEIVER_FUNCTION[i]), Modality.ABSTRACT, Visibilities.PUBLIC);
+
+            constructorDescriptorForReceiverFunction.initialize(receiverFunction.getTypeConstructor().getParameters(),
+                                             Collections.<ValueParameterDescriptor>emptyList(), Visibilities.PUBLIC);
+            constructorDescriptorForReceiverFunction.setReturnType(receiverFunction.getDefaultType());
         }
     }
 
@@ -249,18 +260,18 @@ public class JetStandardClasses {
         return scopeForInvoke;
     }
 
-    private static List<TypeParameterDescriptor> createTypeParameters(int parameterCount, ClassDescriptorImpl function) {
+    private static List<TypeParameterDescriptor> createTypeParameters(int baseIndex, int parameterCount, ClassDescriptorImpl function) {
         List<TypeParameterDescriptor> parameters = new ArrayList<TypeParameterDescriptor>();
-        for (int j = 1; j <= parameterCount; j++) {
+        for (int j = 0; j < parameterCount; j++) {
             parameters.add(TypeParameterDescriptorImpl.createWithDefaultBound(
                     function,
                     Collections.<AnnotationDescriptor>emptyList(),
-                    false, Variance.IN_VARIANCE, Name.identifier("P" + j), j));
+                    false, Variance.IN_VARIANCE, Name.identifier("P" + (j + 1)), baseIndex + j));
         }
         parameters.add(TypeParameterDescriptorImpl.createWithDefaultBound(
                 function,
                 Collections.<AnnotationDescriptor>emptyList(),
-                false, Variance.OUT_VARIANCE, Name.identifier("R"), parameterCount + 1));
+                false, Variance.OUT_VARIANCE, Name.identifier("R"), baseIndex + parameterCount));
         return parameters;
     }