scala - Most concise way to combine sequence elements

Question

Say we have two sequences and we and we want to combine them using some method

val a = Vector(1,2,3)
val b = Vector(4,5,6)

for example addition could be

val c = a zip b map { i => i._1 + i._2 }

or

val c = a zip b map { case (i, j) => i + j }

The repetition in the second part makes me think this should be possible in a single operation. I can't see any built-in method for this. I suppose what I really want is a zip method that skips the creation and extraction of tuples.

Is there a prettier / more concise way in plain Scala, or maybe with Scalaz? If not, how would you write such a method and pimp it onto sequences so I could write something like

val c = a zipmap b (_+_)

Answer 1

There is

(a,b).zipped.map(_ + _)

which is probably close enough to what you want to not bother with an extension. (You can't use it point-free, unfortunately, since the implicits on zipped don't like that.)