I'm trying to use the Scalaz operator |+| as suggested in this question
Best way to merge two maps and sum the values of same key?
import scalaz._
val map1 = Map("a" -> 1,"b" -> 2, "c" -> 5)
val map2 = Map("a" -> 3,"b" -> 4)
val map3 = map1 |+| map2
Intellij says |+| cannot resolve symbol and import.scalaz._ is unused. The SBT seems to be working just fine and the import statement looks valid but here it is just in case.
"org.scalaz" %% "scalaz-core" % "7.2.6"
Whats happening?