Scala maps -> operator

Question

What does the symbol -> mean in the context of a Map in Scala?

Scala’s Predef class offers an implicit conversion that lets

Answer 1

-> is used to couple keys and values for a map. So:

val m = Map(1 -> "one", 2 -> "two", 3 -> "three")

will map the first 3 positive integers into text equivalents (that is, m(1) will be "one", etc.). You could also write it as

val m = Map((1,"one"), (2,"two"), (3,"three"))

but the first way looks nicer, which is why it's provided as an alternative.