Scala passing method to supers constructor -

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i'd have hierarchy base class can take function in constructor , derived class can supply method function. there 1 way below it's ugly. have declare child's function in constructor arg list of super's constructor. means function anonymous , not method of child class (though don't think care that). real code long , end difficult read, if had more 1 of these functions.

thus:

class a[t](s1: string, s2: string, w: (string, string) => unit){   def go: unit = {     w(s1, s2)   } }  val externalwriter = { (s1: string, s2: string) =>     println (s1+s2) }  val w1 = new a[string]("hello ", "world", externalwriter) w1.go  case class b(s1: string, s2: string) extends a[string](s1, s2, w = { (a: string, b: string) =>     println ("class b:"+a+b)   }){   def write: unit = go }  val w2 = b("hey  ","guys") w2.write

w1.go prints "hello world" , w2.write prints "class b: hey guys". want there way have w method or val of class b , still pass super's constructor?

i similar monkjack's solution, using more of mixin pattern. key difference here being i'm using anonymous refinement of a create w1, allowing me keep w method.

abstract class a(s1: string, s2: string) {   def w(arg1: string, arg2: string): unit   def go(): unit = {     w(s1, s2)   } }  val w1 = new a("hello", "world") {   def w(a: string, b: string): unit = println(a + b) } w1.go()  case class b(s1: string, s2: string) extends a(s1, s2) {   def w(a: string, b: string): unit = println("class b:" + + b)   def write: unit = go }  val w2 = b("hey  ", "guys") w2.write  trait c {   def w(a: string, b: string): unit = println("trait c:" + + b) }  val w3 = new a("bye ", "everyone") c w3.go()

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