Add map operation to SimpleIdentitySet

Author: odersky

compiler/src/dotty/tools/dotc/util/SimpleIdentitySet.scala

@@ -12,6 +12,7 @@ abstract class SimpleIdentitySet[+Elem <: AnyRef] {
   def contains[E >: Elem <: AnyRef](x: E): Boolean
   def foreach(f: Elem => Unit): Unit
   def exists[E >: Elem <: AnyRef](p: E => Boolean): Boolean
+  def map[B <: AnyRef](f: Elem => B): SimpleIdentitySet[B]
   def /: [A, E >: Elem <: AnyRef](z: A)(f: (A, E) => A): A
   def toList: List[Elem]
 
@@ -55,6 +56,7 @@ object SimpleIdentitySet {
     def contains[E <: AnyRef](x: E): Boolean = false
     def foreach(f: Nothing => Unit): Unit = ()
     def exists[E <: AnyRef](p: E => Boolean): Boolean = false
+    def map[B <: AnyRef](f: Nothing => B): SimpleIdentitySet[B] = empty
     def /: [A, E <: AnyRef](z: A)(f: (A, E) => A): A = z
     def toList = Nil
   }
@@ -69,6 +71,8 @@ object SimpleIdentitySet {
     def foreach(f: Elem => Unit): Unit = f(x0.asInstanceOf[Elem])
     def exists[E >: Elem <: AnyRef](p: E => Boolean): Boolean =
       p(x0.asInstanceOf[E])
+    def map[B <: AnyRef](f: Elem => B): SimpleIdentitySet[B] =
+      Set1(f(x0.asInstanceOf[Elem]))
     def /: [A, E >: Elem <: AnyRef](z: A)(f: (A, E) => A): A =
       f(z, x0.asInstanceOf[E])
     def toList = x0.asInstanceOf[Elem] :: Nil
@@ -86,6 +90,8 @@ object SimpleIdentitySet {
     def foreach(f: Elem => Unit): Unit = { f(x0.asInstanceOf[Elem]); f(x1.asInstanceOf[Elem]) }
     def exists[E >: Elem <: AnyRef](p: E => Boolean): Boolean =
       p(x0.asInstanceOf[E]) || p(x1.asInstanceOf[E])
+    def map[B <: AnyRef](f: Elem => B): SimpleIdentitySet[B] =
+      Set2(f(x0.asInstanceOf[Elem]), f(x1.asInstanceOf[Elem]))
     def /: [A, E >: Elem <: AnyRef](z: A)(f: (A, E) => A): A =
       f(f(z, x0.asInstanceOf[E]), x1.asInstanceOf[E])
     def toList = x0.asInstanceOf[Elem] :: x1.asInstanceOf[Elem] :: Nil
@@ -114,6 +120,8 @@ object SimpleIdentitySet {
     }
     def exists[E >: Elem <: AnyRef](p: E => Boolean): Boolean =
       p(x0.asInstanceOf[E]) || p(x1.asInstanceOf[E]) || p(x2.asInstanceOf[E])
+    def map[B <: AnyRef](f: Elem => B): SimpleIdentitySet[B] =
+      Set3(f(x0.asInstanceOf[Elem]), f(x1.asInstanceOf[Elem]), f(x2.asInstanceOf[Elem]))
     def /: [A, E >: Elem <: AnyRef](z: A)(f: (A, E) => A): A =
       f(f(f(z, x0.asInstanceOf[E]), x1.asInstanceOf[E]), x2.asInstanceOf[E])
     def toList = x0.asInstanceOf[Elem] :: x1.asInstanceOf[Elem] :: x2.asInstanceOf[Elem] :: Nil
@@ -156,6 +164,8 @@ object SimpleIdentitySet {
     }
     def exists[E >: Elem <: AnyRef](p: E => Boolean): Boolean =
       xs.asInstanceOf[Array[E]].exists(p)
+    def map[B <: AnyRef](f: Elem => B): SimpleIdentitySet[B] =
+      SetN(xs.map(x => f(x.asInstanceOf[Elem]).asInstanceOf[AnyRef]))
     def /: [A, E >: Elem <: AnyRef](z: A)(f: (A, E) => A): A =
       xs.asInstanceOf[Array[E]].foldLeft(z)(f)
     def toList: List[Elem] = {