Scala - Transform a Iterator into a Map

Question

How to get from an Iterator like this

val it = Iterator("one","two","three","four","five")

a map like

Map(four -> 4, three -> 5, two -> 3, five -> 4, one -> 3)

 var m = Map[String, Int]() while (it.hasNext) { val cell = it.next() m += (cell -> cell.length()) }

this is a solution using var but I'd like to use just Immutable and val variable.

If I use the for yield statement the returning object would be a Iterator[Map] and I do not want that:

val m = for(i<- it if it.hasNext) yield Map(i->i.length())

Your for version is very odd. You don't need the if - the for already handles that, and you yield a separate Map for each entry, instead ot just the tuple. {for (i <- it) yield (i -> i.length)}.toMap would do it. — The Archetypal Paul
– The Archetypal Paul, Commented Feb 17, 2017 at 13:18

nmat · Accepted Answer · 2017-02-17 12:01:22Z

9

You can just use map:

val m = it.map(c => c -> c.length).toMap

answered Feb 17, 2017 at 12:01

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