Address doc comment rot in the standard library.

- Match @param/@tparam names to the actual parameter name
- Use @tparam for type parameters
- Whitespace is required between `*` and `@`
- Fix incorrect references to @define macros.
- Use of monospace `` and {{{}}} (much more needed)
- Remove `@param p1 ...` stubs, which appear in the generated docss.
  - But, retainsed `@param p1` stubs, assuming they will be filtered from
    the generated docs by SI-5795.
- Avoid use of the shorthand `@param   doc for the solitary param`
  (which works, but isn't recognized by the code inspection in IntelliJ
  I used to sweep through the problems)

The remaining warnings from `ant docs` seem spurious, I suspect they are
an unintended consequence of documenting extension methods.

  [scaladoc] /Users/jason/code/scala/src/library/scala/collection/TraversableOnce.scala:181: warning: Variable coll undefined in comment for method reduceOption in class Tuple2Zipped
  [scaladoc]   def reduceOption[A1 >: A](op: (A1, A1) => A1): Option[A1] = reduceLeftOption(op)
  [scaladoc]       ^

4 files changed, 14 insertions, 16 deletions

diff --git a/src/library/scala/collection/parallel/ParIterableLike.scala b/src/library/scala/collection/parallel/ParIterableLike.scala
index 4cb229fc0f..321f259f5d 100644
--- a/src/library/scala/collection/parallel/ParIterableLike.scala
+++ b/src/library/scala/collection/parallel/ParIterableLike.scala
@@ -491,8 +491,8 @@ self: ParIterableLike[T, Repr, Sequential] =>
    *
    *  $abortsignalling
    *
-   *  @param p    a predicate used to test elements
-   *  @return     true if `p` holds for all elements, false otherwise
+   *  @param pred    a predicate used to test elements
+   *  @return        true if `p` holds for all elements, false otherwise
    */
   def forall(pred: T => Boolean): Boolean = {
     tasksupport.executeAndWaitResult(new Forall(pred, splitter assign new DefaultSignalling with VolatileAbort))
@@ -502,8 +502,8 @@ self: ParIterableLike[T, Repr, Sequential] =>
    *
    *  $abortsignalling
    *
-   *  @param p    a predicate used to test elements
-   *  @return     true if `p` holds for some element, false otherwise
+   *  @param pred    a predicate used to test elements
+   *  @return        true if `p` holds for some element, false otherwise
    */
   def exists(pred: T => Boolean): Boolean = {
     tasksupport.executeAndWaitResult(new Exists(pred, splitter assign new DefaultSignalling with VolatileAbort))
@@ -517,8 +517,8 @@ self: ParIterableLike[T, Repr, Sequential] =>
    *
    *  $abortsignalling
    *
-   *  @param p     predicate used to test the elements
-   *  @return      an option value with the element if such an element exists, or `None` otherwise
+   *  @param pred     predicate used to test the elements
+   *  @return         an option value with the element if such an element exists, or `None` otherwise
    */
   def find(pred: T => Boolean): Option[T] = {
     tasksupport.executeAndWaitResult(new Find(pred, splitter assign new DefaultSignalling with VolatileAbort))
@@ -685,7 +685,7 @@ self: ParIterableLike[T, Repr, Sequential] =>
    *  @tparam That      type of the resulting collection
    *  @param z          neutral element for the operator `op`
    *  @param op         the associative operator for the scan
-   *  @param cbf        combiner factory which provides a combiner
+   *  @param bf         $bfinfo
    *  @return           a collection containing the prefix scan of the elements in the original collection
    *
    *  @usecase def scan(z: T)(op: (T, T) => T): $Coll[T]
diff --git a/src/library/scala/collection/parallel/ParSeqLike.scala b/src/library/scala/collection/parallel/ParSeqLike.scala
index b3c527da84..be5ab03ba7 100644
--- a/src/library/scala/collection/parallel/ParSeqLike.scala
+++ b/src/library/scala/collection/parallel/ParSeqLike.scala
@@ -162,7 +162,7 @@ self =>
    *
    *  $abortsignalling
    *
-   *  @tparam U      the element type of `that` parallel sequence
+   *  @tparam S      the element type of `that` parallel sequence
    *  @param that    the parallel sequence this sequence is being searched for
    *  @param offset  the starting offset for the search
    *  @return        `true` if there is a sequence `that` starting at `offset` in this sequence, `false` otherwise
@@ -287,9 +287,7 @@ self =>
   /** Computes the multiset intersection between this $coll and another sequence.
    *
    *  @param that   the sequence of elements to intersect with.
-   *  @tparam B     the element type of the returned $coll.
-   *  @tparam That  $thatinfo
-   *  @param bf     $bfinfo
+   *  @tparam U     the element type of `that` parallel sequence
    *  @return       a new collection of type `That` which contains all elements of this $coll
    *                which also appear in `that`.
    *                If an element value `x` appears
diff --git a/src/library/scala/collection/parallel/RemainsIterator.scala b/src/library/scala/collection/parallel/RemainsIterator.scala
index c5910ff2c8..a67a4d8eb7 100644
--- a/src/library/scala/collection/parallel/RemainsIterator.scala
+++ b/src/library/scala/collection/parallel/RemainsIterator.scala
@@ -39,8 +39,7 @@ private[collection] trait RemainsIterator[+T] extends Iterator[T] {
 /** Augments iterators with additional methods, mostly transformers,
  *  assuming they iterate an iterable collection.
  *
- *  @param T          type of the elements iterated.
- *  @param IterRepr   iterator type.
+ *  @tparam T         type of the elements iterated.
  */
 private[collection] trait AugmentedIterableIterator[+T] extends RemainsIterator[T] {
 
@@ -377,7 +376,7 @@ private[collection] trait AugmentedSeqIterator[+T] extends AugmentedIterableIter
 /** Parallel iterators allow splitting and provide a `remaining` method to
  *  obtain the number of elements remaining in the iterator.
  *
- *  @param T          type of the elements iterated.
+ *  @tparam T          type of the elements iterated.
  */
 trait IterableSplitter[+T]
 extends AugmentedIterableIterator[T]
@@ -537,7 +536,7 @@ self =>
 
 /** Parallel sequence iterators allow splitting into arbitrary subsets.
  *
- *  @param T          type of the elements iterated.
+ *  @tparam T          type of the elements iterated.
  */
 trait SeqSplitter[+T]
 extends IterableSplitter[T]
diff --git a/src/library/scala/collection/parallel/mutable/ParHashMap.scala b/src/library/scala/collection/parallel/mutable/ParHashMap.scala
index 05b3f89fa1..8d39d6e0de 100644
--- a/src/library/scala/collection/parallel/mutable/ParHashMap.scala
+++ b/src/library/scala/collection/parallel/mutable/ParHashMap.scala
@@ -26,7 +26,8 @@ import collection.parallel.Task
  *  `ParHashMap` is a parallel map which internally keeps elements within a hash table.
  *  It uses chaining to resolve collisions.
  *
- *  @tparam T        type of the elements in the parallel hash map
+ *  @tparam K        type of the keys in the parallel hash map
+ *  @tparam V        type of the values in the parallel hash map
  *
  *  @define Coll `ParHashMap`
  *  @define coll parallel hash map