Added productElementName to Product.

case class field names your heart desires. Review by odersky.

scala> case class Foo[T](kilroy: String, burma: List[T], shave:
Seq[Int]) defined class Foo

scala> Foo("was here", List('myanmar), Seq(25, 25))

res0: Foo[Symbol] = Foo(was here,List('myanmar),List(25, 25))

scala> 0 to 2 map (res0 productElementName _)
res1: IndexedSeq[String] = IndexedSeq(kilroy, burma, shave)

1 files changed, 13 insertions, 1 deletions

diff --git a/src/library/scala/Product.scala b/src/library/scala/Product.scala
index 8521cf2437..417b87f191 100644
--- a/src/library/scala/Product.scala
+++ b/src/library/scala/Product.scala
@@ -20,7 +20,7 @@ package scala
  */
 trait Product extends Equals {
 
-  /** for a product <code>A(x_1,...,x_k)</code>, returns <code>x_(n+1)</code>
+  /** For a product <code>A(x_1,...,x_k)</code>, returns <code>x_(n+1)</code>
    *  for <code>0 &lt;= n &lt; k</code>
    *
    *  @param  n the index of the element to return
@@ -29,6 +29,18 @@ trait Product extends Equals {
    */
   def productElement(n: Int): Any
 
+  /** Returns the name of the field at the given index from the definition
+   *  of the class.
+   *
+   *  @param  n   the index of the element name to return
+   *  @throws     NoSuchElementException      if the name data is unavailable for any reason
+   *  @throws     IndexOutOfBoundsException   if the index is out of range
+   *  @return     a String representing the field name
+   */
+  def productElementName(n: Int): String =
+    // the method implementation is synthetic - if it is not generated we always throw.
+    throw new NoSuchElementException()
+
   /** return k for a product <code>A(x_1,...,x_k)</code>
    */
   def productArity: Int