Show instances for ground types

[mattisboeckle]

Implement new Core -> Core Phase which
synthesizes show definitions for any type based on ground show definitions

For example

type MaybeInt {
  Nothing()
  Just(x: Int)
}

could generate something along the lines of

def show(value: MaybeInt): String = value match {
  case Nothing() => "Nothing"
  case Just(x: Int) => "Just(${x.show})"
}

[mattisboeckle]

The current implementation can already generate the following core code for

type MaybeInt {
  Nothing()
  Just(x: Int, y: Int)
}

def myshow_3970(value_3971: MaybeInt_3714) = {
  def b_k0_3972() = return "Nothing"
  def b_k1_3973(x_3722: Int_389, y_3723: Int_389) = return infixConcat_39("Just(", infixConcat_39(show_15(x_3722), infixConcat_39(", ", infixConcat_39(show_15(y_3723), ")"))))
  val v_r_3974: String_394 = value_3971 match {
    case Nothing_3718 { () => 
      b_k0_3972()
    }
    case Just_3719 { (x_3722: Int_389, y_3723: Int_389) => 
      b_k1_3973(x_3722, y_3723)
    }
  };
  return v_r_3974
}

but when being called in main like this

let tmp_3960 = make MaybeInt_3714 Just_3719(42, 45)
let tmp_3963 = myshow_3970(tmp_3960)
let tmp_3964 = println_1(tmp_3963)

the compiler fails in Transformer with
Unsupported expression: PureApp(BlockVar(myshow,Function(List(),List(),List(Data(MaybeInt,List())),List(),Data(String,List())),Set()),List(),List(ValueVar(tmp,Data(MaybeInt,List()))))

[b-studios]

Since it is a "user defined" function, you need to call it with App, not PureApp