Is there a type bound that makes this work?

2009/10/8 Meredith Gregory :
> trait ToDo[ToBe <: ???] { object Body extends ToBe }

You can't extend a type parameter or abstract type member directly,
but you can get an equivalent effect using abstract members and
refinements,

trait ToBe
trait ToDo { val Body : ToBe }

trait MyToBe extends ToBe

new ToDo { object Body extends MyToBe } // encoding of new ToDo[MyToBe]

Cheers,

Miles

this works with AnyRef as type bound

trait ToDoModule { type ToBe ; trait ToDo[ToBe <: AnyRef] }

class Foo

object ToDoModuleWithFoo
extends ToDoModule { type ToBe = Foo ; object ToDo extends Foo }


it is, more involved than Miles suggestion

2009/10/8 Miles Sabin <miles [at] milessabin [dot] com>

2009/10/8 Meredith Gregory <lgreg [dot] meredith [at] gmail [dot] com>:
> trait ToDo[ToBe <: ???] { object Body extends ToBe }

You can't extend a type parameter or abstract type member directly,
but you can get an equivalent effect using abstract members and
refinements,

trait ToBe
trait ToDo { val Body : ToBe }

trait MyToBe extends ToBe

new ToDo { object Body extends MyToBe } // encoding of new ToDo[MyToBe]

Cheers,


Miles

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