https://www.graalvm.org/ 
abstract class com.oracle.truffle.trufflenode.node.FlattenNode extends com.oracle.truffle.js.nodes.JavaScriptBaseNode
  minor version: 0
  major version: 59
  flags: flags: (0x0420) ACC_SUPER, ACC_ABSTRACT
  this_class: com.oracle.truffle.trufflenode.node.FlattenNode
  super_class: com.oracle.truffle.js.nodes.JavaScriptBaseNode
{
  void <init>();
    descriptor: ()V
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.trufflenode.node.FlattenNode this
         0: .line 58
            aload 0 /* this */
            invokespecial com.oracle.truffle.js.nodes.JavaScriptBaseNode.<init>:()V
            return
        end local 0 // com.oracle.truffle.trufflenode.node.FlattenNode this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/trufflenode/node/FlattenNode;

  protected abstract java.lang.Object execute(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0404) ACC_PROTECTED, ACC_ABSTRACT
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.String doLazyString(com.oracle.truffle.js.runtime.objects.JSLazyString);
    descriptor: (Lcom/oracle/truffle/js/runtime/objects/JSLazyString;)Ljava/lang/String;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.objects.JSLazyString value
         0: .line 63
            aload 0 /* value */
            invokevirtual com.oracle.truffle.js.runtime.objects.JSLazyString.toString:()Ljava/lang/String;
            areturn
        end local 0 // com.oracle.truffle.js.runtime.objects.JSLazyString value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Lcom/oracle/truffle/js/runtime/objects/JSLazyString;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.String doString(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // java.lang.String value
         0: .line 68
            aload 0 /* value */
            areturn
        end local 0 // java.lang.String value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Ljava/lang/String;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.Object doSymbol(com.oracle.truffle.js.runtime.Symbol);
    descriptor: (Lcom/oracle/truffle/js/runtime/Symbol;)Ljava/lang/Object;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.Symbol value
         0: .line 73
            aload 0 /* value */
            areturn
        end local 0 // com.oracle.truffle.js.runtime.Symbol value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Lcom/oracle/truffle/js/runtime/Symbol;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.Object doBigInt(com.oracle.truffle.js.runtime.BigInt);
    descriptor: (Lcom/oracle/truffle/js/runtime/BigInt;)Ljava/lang/Object;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.BigInt value
         0: .line 78
            aload 0 /* value */
            areturn
        end local 0 // com.oracle.truffle.js.runtime.BigInt value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Lcom/oracle/truffle/js/runtime/BigInt;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static boolean doBoolean(boolean);
    descriptor: (Z)Z
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // boolean value
         0: .line 83
            iload 0 /* value */
            ireturn
        end local 0 // boolean value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Z
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static int doInt(int);
    descriptor: (I)I
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // int value
         0: .line 88
            iload 0 /* value */
            ireturn
        end local 0 // int value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  I
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static com.oracle.truffle.js.runtime.SafeInteger doSafeInteger(com.oracle.truffle.js.runtime.SafeInteger);
    descriptor: (Lcom/oracle/truffle/js/runtime/SafeInteger;)Lcom/oracle/truffle/js/runtime/SafeInteger;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.SafeInteger value
         0: .line 93
            aload 0 /* value */
            areturn
        end local 0 // com.oracle.truffle.js.runtime.SafeInteger value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Lcom/oracle/truffle/js/runtime/SafeInteger;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static long doLong(long);
    descriptor: (J)J
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=2, locals=2, args_size=1
        start local 0 // long value
         0: .line 98
            lload 0 /* value */
            lreturn
        end local 0 // long value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  J
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static double doDouble(double);
    descriptor: (D)D
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=2, locals=2, args_size=1
        start local 0 // double value
         0: .line 103
            dload 0 /* value */
            dreturn
        end local 0 // double value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  D
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.Object doJSObject(com.oracle.truffle.api.object.DynamicObject);
    descriptor: (Lcom/oracle/truffle/api/object/DynamicObject;)Ljava/lang/Object;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.api.object.DynamicObject value
         0: .line 108
            aload 0 /* value */
            areturn
        end local 0 // com.oracle.truffle.api.object.DynamicObject value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Lcom/oracle/truffle/api/object/DynamicObject;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization(guards = {"isJSDynamicObject(value)"})
    MethodParameters:
       Name  Flags
      value  

  protected static java.lang.Object doForeignObject(com.oracle.truffle.api.interop.TruffleObject, com.oracle.truffle.api.interop.InteropLibrary);
    descriptor: (Lcom/oracle/truffle/api/interop/TruffleObject;Lcom/oracle/truffle/api/interop/InteropLibrary;)Ljava/lang/Object;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.interop.TruffleObject value
        start local 1 // com.oracle.truffle.api.interop.InteropLibrary interop
         0: .line 114
            aload 1 /* interop */
            aload 0 /* value */
            invokevirtual com.oracle.truffle.api.interop.InteropLibrary.isString:(Ljava/lang/Object;)Z
            ifeq 4
         1: .line 119
            aload 1 /* interop */
            aload 0 /* value */
            invokevirtual com.oracle.truffle.api.interop.InteropLibrary.asString:(Ljava/lang/Object;)Ljava/lang/String;
         2: areturn
         3: .line 120
      StackMap locals:
      StackMap stack: com.oracle.truffle.api.interop.UnsupportedMessageException
            pop
         4: .line 124
      StackMap locals:
      StackMap stack:
            aload 0 /* value */
            areturn
        end local 1 // com.oracle.truffle.api.interop.InteropLibrary interop
        end local 0 // com.oracle.truffle.api.interop.TruffleObject value
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    5     0    value  Lcom/oracle/truffle/api/interop/TruffleObject;
            0    5     1  interop  Lcom/oracle/truffle/api/interop/InteropLibrary;
      Exception table:
        from    to  target  type
           1     2       3  Class com.oracle.truffle.api.interop.UnsupportedMessageException
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization(guards = {"isForeignObject(value)"}, limit = "3")
    RuntimeInvisibleParameterAnnotations: 
      0:
      1:
        com.oracle.truffle.api.library.CachedLibrary(value = "value")
    MethodParameters:
         Name  Flags
      value    
      interop  

  protected static java.lang.Object doOther(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x000c) ACC_PROTECTED, ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // java.lang.Object value
         0: .line 129
            aload 0 /* value */
            areturn
        end local 0 // java.lang.Object value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  Ljava/lang/Object;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization(guards = {"!isLazyString(value)", "!isTruffleObject(value)"})
    MethodParameters:
       Name  Flags
      value  
}
SourceFile: "FlattenNode.java"
    RuntimeInvisibleAnnotations: 
      com.oracle.truffle.api.dsl.ImportStatic(value = {Lcom/oracle/truffle/js/runtime/JSRuntime;})