-

scala> def a = { val x = Array(1.2, 2.3); return x }
<console>:11: error: method a has return statement; needs result type
       def a = { val x = Array(1.2, 2.3); return x }
                                          ^

scala> def a = { val x = Array(1.2, 2.3); x }
a: Array[Double]

scala> :scalap a
scalap: no such command.  Type :help for help.

scala> :javap a
  Size 613 bytes
  MD5 checksum e6effd7520b9e489ff2488d014505082
  Compiled from "<console>"
public class
  minor version: 0
  major version: 50
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Utf8
   #2 = Class              #1             //
   #3 = Utf8               java/lang/Object
   #4 = Class              #3             // java/lang/Object
   #5 = Utf8               <console>
   #6 = Utf8               MODULE$
   #7 = Utf8               L;
   #8 = Utf8               <clinit>
   #9 = Utf8               ()V
  #10 = Utf8               <init>
  #11 = NameAndType        #10:#9         // "<init>":()V
  #12 = Methodref          #2.#11         // ."<init>":()V
  #13 = Utf8               a
  #14 = Utf8               ()[D
  #15 = Double             1.2d
  #17 = Double             2.3d
  #19 = Utf8               this
  #20 = Utf8               x
  #21 = Utf8               [D
  #22 = Methodref          #4.#11         // java/lang/Object."<init>":()V
  #23 = NameAndType        #6:#7          // MODULE$:L;
  #24 = Fieldref           #2.#23         // .MODULE$:L;
  #25 = Utf8
  #26 = Class              #25            //
  #27 = Utf8               $line4/$read
  #28 = Class              #27            // $line4/$read
  #29 = Utf8
  #30 = Utf8               Code
  #31 = Utf8               LocalVariableTable
  #32 = Utf8               LineNumberTable
  #33 = Utf8               SourceFile
  #34 = Utf8               InnerClasses
  #35 = Utf8               ScalaInlineInfo
  #36 = Utf8               Scala
{
  public static final  MODULE$;
    descriptor: L;
    flags: ACC_PUBLIC, ACC_STATIC, ACC_FINAL

  public static {};
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: new           #2                  // class
         3: invokespecial #12                 // Method "<init>":()V
         6: return

  public double[] a();
    descriptor: ()[D
    flags: ACC_PUBLIC
    Code:
      stack=5, locals=2, args_size=1
         0: iconst_2
         1: newarray       double
         3: dup
         4: iconst_0
         5: ldc2_w        #15                 // double 1.2d
         8: dastore
         9: dup
        10: iconst_1
        11: ldc2_w        #17                 // double 2.3d
        14: dastore
        15: astore_1
        16: aload_1
        17: areturn
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0      18     0  this   L;
           16       1     1     x   [D
      LineNumberTable:
        line 11: 0

  public ();
    descriptor: ()V
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokespecial #22                 // Method java/lang/Object."<init>":()V
         4: aload_0
         5: putstatic     #24                 // Field MODULE$:L;
         8: return
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       9     0  this   L;
      LineNumberTable:
        line 15: 0
}
SourceFile: "<console>"
InnerClasses:
     public static #29= #26 of #28; //=class  of class $line4/$read
     public static #29= #2 of #26; //=class  of class
Error: unknown attribute
  ScalaInlineInfo: length = 0xE
   01 01 00 02 00 0A 00 09 01 00 0D 00 0E 01
Error: unknown attribute
  Scala: length = 0x0