Scala for-loop. Getting index in consice way

Question

In this code I want to increment index to put it to each yielding result.

var index=0

for(str <- splitToStrings(text) ) yield           


        

Answer 1

zipWithIndex will copy and create a new collection, so better make it lazy when the collection is potentially large

for ((str, index) <- splitToStrings(text).view.zipWithIndex)
  yield new Word(str, UNKNOWN_FORM, index)

In fact, if you are working with an indexed sequence, then a more efficient way is to use indices, which produces the range of all indices of this sequence.

val strs = splitToStrings(text)

for(i <- strs.indices) yield  {
  new Word(strs(i), UNKNOWN_FORM, i )
}