Scala -- mutually exclusive traits -

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is there way define collection of alternatives of common type:

trait mutability trait mutable extends mutability trait immutable extends mutability

and have compiler preclude like:

object hat extends mutable immutable

i believe can force some compiler error having common, conflicting member error message bit oblique:

trait mutability trait mutable extends mutability { protected val conflict = true } trait immutable extends mutability { protected val conflict = true }  object hat extends mutable immutable  <console>:10: error: object hat inherits conflicting members: value conflict in class immutable$class of type boolean  , value conflict in class mutable$class of type boolean (note: can resolved declaring override in object hat.)    object hat extends immutable mutable

is there more direct way express constraint , not permit work around taking hint offered compiler (override 'conflict' in hat)?

thanks insights

i think might work

sealed trait mutability case object immutable extends mutability case object mutable extends mutability  trait mutabilitylevel[a <: mutability]  class foo extends mutabilitylevel[immutable.type]

this (ab?)uses fact can't extend same trait twice different parameterization 

scala> class foo extends mutabilitylevel[immutable.type] mutabilitylevel[mutable.type] <console>:11: error: illegal inheritance;  self-type foo not conform mutabilitylevel[immutable.type]'s selftype mutabilitylevel[immutable.type]        class foo extends mutabilitylevel[immutable.type] mutabilitylevel[mutable.type]                          ^ <console>:11: error: illegal inheritance;  self-type foo not conform mutabilitylevel[mutable.type]'s selftype mutabilitylevel[mutable.type]        class foo extends mutabilitylevel[immutable.type] mutabilitylevel[mutable.type]

however..

scala> class foo extends mutabilitylevel[mutability] defined class foo

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