A proposal to enhance Tuple2#{zip,zipped}

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Since #3511 has been fixed, I have a proposal to enhance the methods zip&zipped in Tupel2(Tuple3). As we known, we can use (xs,ys).zip and (xs,ys).zipped in Scala2.8 where xs and ys are both some type of Traversable. There are some limited in current implementation.
Let

xs = List.range(0,10)
ys = Stream.from(0)

,then the following codes are invalid:

(ys,xs).zip
(ys,ys).zip

While I expected:

(ys,xs).zip == Stream((0,0),..,(9,9))
(ys,ys).zip == Stream((0,0),..)

Here is my proposal which could fix these shortages:

class PairX[+T1,+T2](t: (T1,T2)) {
  import scala.collection.{TraversableLike,TraversableView}
  import scala.collection.generic.CanBuildFrom
  import t._
  def zipx[Repr1, El1, El2, To](implicit w1:   T1 => TraversableLike[El1, Repr1],
                                        w2:   T2 => Iterable[El2],
                                        cbf1: CanBuildFrom[Repr1, (El1, El2), To]): To = {
    val coll1: TraversableLike[El1, Repr1] = _1
    val coll2: Iterable[El2] = _2
    val elems2 = coll2.iterator

    coll1.view.takeWhile{ _ => elems2.hasNext }.map{ el1 => (el1,elems2.next) }.asInstanceOf[TraversableView[(El1,El2),Repr1]].force
  }
}

implicit def p2px[T1,T2](t: (T1,T2)): PairX[T1,T2] = new PairX(t)  

Similar changes should be made in Tuple2#Zipped#{map,flatMap,filter}, Tuple3#zip and Tuple3#Zipped#{map,flatMap,filter}.
The effection:

scala> val xs = List.range(0,10)
xs: List[Int] = List(0, 1, 2, 3, 4, 5, 6, 7, 8, 9)

scala> val ys = Stream.from(0)
ys: scala.collection.immutable.Stream[Int] = Stream(0, ?)

scala> (ys,xs).zipx
res2: scala.collection.immutable.Stream[(Int, Int)] = Stream((0,0), ?)

scala> res2.force
res3: scala.collection.immutable.Stream[(Int, Int)] = Stream((0,0), (1,1), (2,2), (3,3), (4,4), (5,5), (6,6), (7,7), (8,8), (9,9))

Note: I think that this proposal doesn't fix #2634, since there is some problems of Stream#iterator(see #3273).

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Imported From: https://issues.scala-lang.org/browse/SI-3526?orig=1
Reporter: Eastsun (eastsun)

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@dragos said:
Adriaan, I think you implemented zipp[ed], can you please have a look? Feel free to reassign if I'm wrong.

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@paulp said:
I'm glad you brought this to my attention. There are numerous issues in there I was unaware of. Working on it now.

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@paulp said:
See proposed alterations in http://permalink.gmane.org/gmane.comp.lang.scala.internals/3890 , awaiting opinion from adriaan.

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@paulp said:
(In r23384) Some issues with Tuple2/3. There was a stray wrong-arity
foreach method in Tuple3, and both classes have what is now
a redundant zip method which is also unfortunately completely
strict in a not entirely fixable fashion. So "zip" is
deprecated in favor of zipped. Closes #3526, but the code
which closes that is primarily found in r23228. No review.