https://www.graalvm.org/ 
class com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 implements com.oracle.truffle.js.runtime.objects.JSModuleLoader
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1
  super_class: java.lang.Object
{
  private final java.util.Map<java.lang.String, com.oracle.truffle.js.runtime.objects.JSModuleRecord> moduleMap;
    descriptor: Ljava/util/Map;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/Map<Ljava/lang/String;Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;>;

  final com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode this$1;
    descriptor: Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  private final com.oracle.truffle.api.object.DynamicObject val$modulesSourceMap;
    descriptor: Lcom/oracle/truffle/api/object/DynamicObject;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final java.lang.String val$name;
    descriptor: Ljava/lang/String;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final com.oracle.truffle.js.runtime.Evaluator val$evaluator;
    descriptor: Lcom/oracle/truffle/js/runtime/Evaluator;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final com.oracle.truffle.js.runtime.JSContext val$context;
    descriptor: Lcom/oracle/truffle/js/runtime/JSContext;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode, com.oracle.truffle.api.object.DynamicObject, java.lang.String, com.oracle.truffle.js.runtime.Evaluator, com.oracle.truffle.js.runtime.JSContext);
    descriptor: (Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode;Lcom/oracle/truffle/api/object/DynamicObject;Ljava/lang/String;Lcom/oracle/truffle/js/runtime/Evaluator;Lcom/oracle/truffle/js/runtime/JSContext;)V
    flags: (0x0000) 
    Code:
      stack=3, locals=6, args_size=6
        start local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
         0: .line 619
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.this$1:Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode;
            aload 0 /* this */
            aload 2
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$modulesSourceMap:Lcom/oracle/truffle/api/object/DynamicObject;
            aload 0 /* this */
            aload 3
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$name:Ljava/lang/String;
            aload 0 /* this */
            aload 4
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$evaluator:Lcom/oracle/truffle/js/runtime/Evaluator;
            aload 0 /* this */
            aload 5
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$context:Lcom/oracle/truffle/js/runtime/JSContext;
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 620
            aload 0 /* this */
            new java.util.HashMap
            dup
            invokespecial java.util.HashMap.<init>:()V
            putfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.moduleMap:Ljava/util/Map;
         2: .line 619
            return
        end local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;
    MethodParameters:
                      Name  Flags
      this$0                final
      val$modulesSourceMap  final
      val$name              final
      val$evaluator         final
      val$context           final

  private com.oracle.truffle.api.source.Source resolveModuleSource(com.oracle.truffle.js.runtime.objects.ScriptOrModule, java.lang.String);
    descriptor: (Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;Ljava/lang/String;)Lcom/oracle/truffle/api/source/Source;
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=5, locals=5, args_size=3
        start local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
        start local 1 // com.oracle.truffle.js.runtime.objects.ScriptOrModule referencingModule
        start local 2 // java.lang.String specifier
         0: .line 623
            aload 0 /* this */
            getfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$modulesSourceMap:Lcom/oracle/truffle/api/object/DynamicObject;
            aload 2 /* specifier */
            invokestatic com.oracle.truffle.js.runtime.objects.JSObject.get:(Lcom/oracle/truffle/api/object/DynamicObject;Ljava/lang/Object;)Ljava/lang/Object;
            astore 3 /* moduleEntry */
        start local 3 // java.lang.Object moduleEntry
         1: .line 624
            aload 3 /* moduleEntry */
            getstatic com.oracle.truffle.js.runtime.objects.Undefined.instance:Lcom/oracle/truffle/js/runtime/objects/JSDynamicObject;
            if_acmpne 3
         2: .line 625
            ldc "Could not find imported module %s"
            iconst_1
            anewarray java.lang.Object
            dup
            iconst_0
            aload 2 /* specifier */
            aastore
            invokestatic java.lang.String.format:(Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/String;
            invokestatic com.oracle.truffle.js.runtime.Errors.createSyntaxError:(Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/JSException;
            athrow
         3: .line 627
      StackMap locals: java.lang.Object
      StackMap stack:
            aload 3 /* moduleEntry */
            invokestatic com.oracle.truffle.js.runtime.JSRuntime.toString:(Ljava/lang/Object;)Ljava/lang/String;
            astore 4 /* code */
        start local 4 // java.lang.String code
         4: .line 628
            ldc "js"
            aload 4 /* code */
            aload 0 /* this */
            getfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$name:Ljava/lang/String;
            invokestatic com.oracle.truffle.api.source.Source.newBuilder:(Ljava/lang/String;Ljava/lang/CharSequence;Ljava/lang/String;)Lcom/oracle/truffle/api/source/Source$LiteralBuilder;
            invokevirtual com.oracle.truffle.api.source.Source$LiteralBuilder.build:()Lcom/oracle/truffle/api/source/Source;
            areturn
        end local 4 // java.lang.String code
        end local 3 // java.lang.Object moduleEntry
        end local 2 // java.lang.String specifier
        end local 1 // com.oracle.truffle.js.runtime.objects.ScriptOrModule referencingModule
        end local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
      LocalVariableTable:
        Start  End  Slot               Name  Signature
            0    5     0               this  Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;
            0    5     1  referencingModule  Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;
            0    5     2          specifier  Ljava/lang/String;
            1    5     3        moduleEntry  Ljava/lang/Object;
            4    5     4               code  Ljava/lang/String;
    MethodParameters:
                   Name  Flags
      referencingModule  
      specifier          

  public com.oracle.truffle.js.runtime.objects.JSModuleRecord resolveImportedModule(com.oracle.truffle.js.runtime.objects.ScriptOrModule, java.lang.String);
    descriptor: (Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=6, locals=3, args_size=3
        start local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
        start local 1 // com.oracle.truffle.js.runtime.objects.ScriptOrModule referencingModule
        start local 2 // java.lang.String specifier
         0: .line 633
            aload 0 /* this */
            getfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.moduleMap:Ljava/util/Map;
            aload 2 /* specifier */
            aload 0 /* this */
            aload 0 /* this */
            getfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$evaluator:Lcom/oracle/truffle/js/runtime/Evaluator;
            aload 0 /* this */
            getfield com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.val$context:Lcom/oracle/truffle/js/runtime/JSContext;
            aload 1 /* referencingModule */
            invokedynamic apply(Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;Lcom/oracle/truffle/js/runtime/Evaluator;Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;)Ljava/util/function/Function;
              Bootstrap: invokestatic java.lang.invoke.LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
                Method arguments:
                  (Ljava/lang/Object;)Ljava/lang/Object;
                  com/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1.lambda$0(Lcom/oracle/truffle/js/runtime/Evaluator;Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord; (7)
                  (Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;
            invokeinterface java.util.Map.computeIfAbsent:(Ljava/lang/Object;Ljava/util/function/Function;)Ljava/lang/Object;
            checkcast com.oracle.truffle.js.runtime.objects.JSModuleRecord
            areturn
        end local 2 // java.lang.String specifier
        end local 1 // com.oracle.truffle.js.runtime.objects.ScriptOrModule referencingModule
        end local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
      LocalVariableTable:
        Start  End  Slot               Name  Signature
            0    1     0               this  Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;
            0    1     1  referencingModule  Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;
            0    1     2          specifier  Ljava/lang/String;
    MethodParameters:
                   Name  Flags
      referencingModule  
      specifier          

  public com.oracle.truffle.js.runtime.objects.JSModuleRecord loadModule(com.oracle.truffle.api.source.Source);
    descriptor: (Lcom/oracle/truffle/api/source/Source;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
        start local 1 // com.oracle.truffle.api.source.Source moduleSource
         0: .line 638
            new java.lang.UnsupportedOperationException
            dup
            invokespecial java.lang.UnsupportedOperationException.<init>:()V
            athrow
        end local 1 // com.oracle.truffle.api.source.Source moduleSource
        end local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
      LocalVariableTable:
        Start  End  Slot          Name  Signature
            0    1     0          this  Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;
            0    1     1  moduleSource  Lcom/oracle/truffle/api/source/Source;
    MethodParameters:
              Name  Flags
      moduleSource  

  private com.oracle.truffle.js.runtime.objects.JSModuleRecord lambda$0(com.oracle.truffle.js.runtime.Evaluator, com.oracle.truffle.js.runtime.JSContext, com.oracle.truffle.js.runtime.objects.ScriptOrModule, java.lang.String);
    descriptor: (Lcom/oracle/truffle/js/runtime/Evaluator;Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;
    flags: (0x1002) ACC_PRIVATE, ACC_SYNTHETIC
    Code:
      stack=5, locals=5, args_size=5
        start local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
        start local 4 // java.lang.String key
         0: .line 633
            aload 1
            aload 2
            aload 0 /* this */
            aload 3
            aload 4 /* key */
            invokevirtual com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1.resolveModuleSource:(Lcom/oracle/truffle/js/runtime/objects/ScriptOrModule;Ljava/lang/String;)Lcom/oracle/truffle/api/source/Source;
            aload 0 /* this */
            invokeinterface com.oracle.truffle.js.runtime.Evaluator.parseModule:(Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/api/source/Source;Lcom/oracle/truffle/js/runtime/objects/JSModuleLoader;)Lcom/oracle/truffle/js/runtime/objects/JSModuleRecord;
            areturn
        end local 4 // java.lang.String key
        end local 0 // com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/js/builtins/DebugBuiltins$DebugLoadModuleNode$1;
            0    1     4   key  Ljava/lang/String;
}
SourceFile: "DebugBuiltins.java"
EnclosingMethod: com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode.loadModule:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/String;
NestHost: com.oracle.truffle.js.builtins.DebugBuiltins
InnerClasses:
  public final LiteralBuilder = com.oracle.truffle.api.source.Source$LiteralBuilder of com.oracle.truffle.api.source.Source
  public abstract DebugLoadModuleNode = com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode of com.oracle.truffle.js.builtins.DebugBuiltins
  com.oracle.truffle.js.builtins.DebugBuiltins$DebugLoadModuleNode$1
  public final Lookup = java.lang.invoke.MethodHandles$Lookup of java.lang.invoke.MethodHandles