error log

[INITIALIZATION][CLIENT][ERROR] [crafttweaker]: Error executing {[0:crafttweaker]: custom_recipes_1.zs}: Method expects a return value
Exception Details:
  Location:
    ZenClass0.process(Lcrafttweaker/api/item/IItemStack;Ljava/util/Map;Lcrafttweaker/api/recipes/ICraftingInfo;)Lcrafttweaker/api/item/IItemStack; @116: return
  Reason:
    Error exists in the bytecode
  Bytecode:
    0x0000000: 2c12 0eb9 0014 0200 c000 163a 0512 18b8
    0x0000010: 001e 1905 b900 2402 0099 005b bb00 2659
    0x0000020: 1227 1228 b700 2b59 b600 2f36 07b6 0032
    0x0000030: 2db9 0038 0100 1507 b900 3e02 0019 05b9
    0x0000040: 0043 0200 9900 212d b900 3801 0015 0719
    0x0000050: 0519 05b9 0046 0100 1247 60b9 004a 0200
    0x0000060: b900 4e03 0059 8407 0115 07a3 ffc5 a700
    0x0000070: 0357 2bb0 b1                           
  Stackmap Table:
    full_frame(@48,{Object[#2],Object[#22],Object[#16],Object[#52],Top,Object[#22],Top,Integer},{Integer})
    same_locals_1_stack_item_frame(@101,Integer)
    same_locals_1_stack_item_frame(@113,Integer)
    chop_frame(@116,2)

java.lang.VerifyError: Method expects a return value
Exception Details:
  Location:
    ZenClass0.process(Lcrafttweaker/api/item/IItemStack;Ljava/util/Map;Lcrafttweaker/api/recipes/ICraftingInfo;)Lcrafttweaker/api/item/IItemStack; @116: return
  Reason:
    Error exists in the bytecode
  Bytecode:
    0x0000000: 2c12 0eb9 0014 0200 c000 163a 0512 18b8
    0x0000010: 001e 1905 b900 2402 0099 005b bb00 2659
    0x0000020: 1227 1228 b700 2b59 b600 2f36 07b6 0032
    0x0000030: 2db9 0038 0100 1507 b900 3e02 0019 05b9
    0x0000040: 0043 0200 9900 212d b900 3801 0015 0719
    0x0000050: 0519 05b9 0046 0100 1247 60b9 004a 0200
    0x0000060: b900 4e03 0059 8407 0115 07a3 ffc5 a700
    0x0000070: 0357 2bb0 b1                           
  Stackmap Table:
    full_frame(@48,{Object[#2],Object[#22],Object[#16],Object[#52],Top,Object[#22],Top,Integer},{Integer})
    same_locals_1_stack_item_frame(@101,Integer)
    same_locals_1_stack_item_frame(@113,Integer)
    chop_frame(@116,2)

	at Custom_recipes_1.__script__(custom_recipes_1.zs:379)
	at __ZenMain__.run(Custom_recipes_1)
	at crafttweaker.runtime.CrTTweaker.loadScript(CrTTweaker.java:147)
	at crafttweaker.runtime.CrTTweaker.load(CrTTweaker.java:54)
	at crafttweaker.CrafttweakerImplementationAPI.load(CrafttweakerImplementationAPI.java:115)
	at crafttweaker.mc1120.events.CommonEventHandler.registerRecipes(CommonEventHandler.java:50)
	at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_312_CommonEventHandler_registerRecipes_Register.invoke(.dynamic)
	at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
	at net.minecraftforge.fml.common.eventhandler.EventBus$1.invoke(EventBus.java:143)
	at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:179)
	at net.minecraftforge.registries.GameData.fireRegistryEvents(GameData.java:746)
	at net.minecraftforge.common.crafting.CraftingHelper.loadRecipes(CraftingHelper.java:622)
	at net.minecraftforge.fml.common.Loader.initializeMods(Loader.java:718)
	at net.minecraftforge.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:352)
	at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:534)
	at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:377)
	at net.minecraft.client.main.Main.main(SourceFile:123)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
	at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

recipe

recipes.addShapeless("unbundle",
  <minecraft:stick> * 8,
  [<contenttweaker:stick_bundle>, <ore:knife>.marked("damageme")],
  function(out, ins, cInfo) {
    val k = ins.damageme as IItemStack;
    if (<ore:knife> has k) {
      for S in 0 .. 8 {
        if (cInfo.inventory.getStack(S).matches(k)) {
          cInfo.inventory.setStack(S, k.withDamage(k.damage + 1));
        }
      }
      return out;
    }
  },
  null);