scala - Pattern for a class that is a list of itself -

consider following:

object main {   case class foo(bar: int) extends foolist {     val self: list[foo] = :: nil   }    abstract class foolist {     val self: list[foo]     def ~(that: foo) = { val list = self :+ that; new foolist { val self = list } }   }    def main(args: array[string]): unit = {     val foo = foo(1) ~ foo(2) ~ foo(3)     println(foo.self)  } } 

could line:

{ val list = self :+ that; new foolist { val self = list } } 

be simplified in way? i'd write like:

new foolist { val self = this.self :+ }   // won't compile 

it seems boil down being able refer differently-scoped identifiers has same name. there mechanism that?

this solves scoping issue. if understand correctly that's want.

abstract class foolist { outer =>   val self: list[foo]   def ~(that: foo) = { new foolist { val self = outer.self :+ } } } 

answer: yes. self-types can used aliases outer scopes.