Clean up message signatures

Author: ennru

compiler/src/dotty/tools/dotc/reporting/diagnostic/messages.scala

@@ -1199,7 +1199,6 @@ object messages {
   extends Message(SuperQualMustBeParentID) {
 
     val msg = hl"""|$qual does not name a parent of $cls"""
-
     val kind = "Reference"
 
     private val parents: Seq[String] = (cls.info.parents map (_.name.show)).sorted
@@ -1214,36 +1213,32 @@ object messages {
   }
 
   case class VarArgsParamMustComeLast()(implicit ctx: Context)
-    extends Message(IncorrectRepeatedParameterSyntaxID) {
-    override def msg: String = "varargs parameter must come last"
-
-    override def kind: String = "Syntax"
-
-    override def explanation: String =
+  extends Message(IncorrectRepeatedParameterSyntaxID) {
+    val msg = "varargs parameter must come last"
+    val kind = "Syntax"
+    val explanation =
       hl"""|The varargs field must be the last field in the method signature.
            |Attempting to define a field in a method signature after a varargs field is an error.
-           |""".stripMargin
+           |"""
   }
 
   case class AmbiguousOverload(tree: tpd.Tree, alts: List[SingleDenotation], pt: Type)(
     err: typer.ErrorReporting.Errors)(
     implicit ctx: Context)
   extends Message(AmbiguousOverloadID) {
 
-    private def all = if (alts.length == 2) "both" else "all"
-
-    override def msg: String =
+    private val all = if (alts.length == 2) "both" else "all"
+    val msg =
       s"""|Ambiguous overload. The ${err.overloadedAltsStr(alts)}
           |$all match ${err.expectedTypeStr(pt)}""".stripMargin
-
-    override def kind: String = "Reference"
-
-    override def explanation: String =
-       s"""|There are ${alts.length} methods that could be referenced as the compiler knows too little about the expected type.
+    val kind = "Reference"
+    val explanation =
+      hl"""|There are ${alts.length} methods that could be referenced as the compiler knows too little
+           |about the expected type.
            |You may specify the expected type e.g. by
            |- assigning it to a value with a specified type, or
-           |- adding a type ascription as in `(instance.myMethod: String => Int)`
-           |""".stripMargin
+           |- adding a type ascription as in `${"instance.myMethod: String => Int"}`
+           |"""
   }
 
 }