scala @switch annotation, does it make any difference to generated byte code?
annotations, match, scala
Solution
Both versions result in identical bytecode. You can test this by pasting one version into the REPL, doing `:javap -` to disassemble it, and then repeating for the other version.
Problem
From scala docs, I understand @switch annotation is to tell compiler to verify that the match expression has been compiled to a tableswitch or lookupswitch and issue an error if it instead compiles into a series of conditional expressions. Now my question is, if compilation is successful, then does it make any difference to generated byte code, as compared to if @switch annotation is not used at all? Consider below two sample code versions, Version 1 ``` import scala.annotation.switch val x = 5 (x: @switch) match { case 1 => println("1") case 2 => println("2") case _ => println("something else") } ``` Version 2 ``` val x = 5 (x) match { case 1 => println("1") case 2 => println("2") case _ => println("something else") } ``` Isn't that both versions will result in same byte code instructions on compilation?