A test summarizing some aspect of the strawman design.

Author: odersky

tests/pos/poly-inheritance.scala

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+// A strawman collection design study in a nutshell
+import reflect.ClassTag
+import Predef.???
+
+class It[+A] extends Ops[A, It, It[A]]
+
+trait Ops[+A, +CC[_], +C] extends Any {
+  def filter(f: A => Boolean): C = ???
+  def map[B](f: A => B): CC[B] = ???
+  def toSeq: It[A] = ???
+}
+
+class ArraySeq[A] extends It[A] with Ops[A, ArraySeq, ArraySeq[A]]
+
+
+class LP {
+  implicit def arrayToSeq[A](xs: Array[A]): ArraySeq[A] = ???
+}
+object Test extends LP {
+
+  implicit class ArrOps[A](val xs: Array[A]) extends AnyVal with Ops[A, ArraySeq, Array[A]] {
+    def map[B: ClassTag](f: A => B): Array[B] = ???
+    override def toSeq: ArraySeq[A] = arrayToSeq(xs)
+  }
+
+  val xs1 = Array(1, 2, 3)
+  val xs2 = xs1.filter(_ % 2 == 0)
+  val xs2a: Array[Int] = xs2
+  val xs3 = xs1.map(_ + "!")
+  val xs3a: Array[String] = xs3
+
+  def f[T](f: Int => T) = {
+    val xs1 = Array(1, 2, 3)
+    val xs2 = xs1.filter(_ % 2 == 0)
+    val xs2a: Array[Int] = xs2
+    val xs3 = xs1.toSeq.map(f)
+    val xs3a: ArraySeq[T] = xs3
+  }
+}
+
+
+
+
+