Let
def h(a: AnyRef*) = a.mkString(",")
h: (a: AnyRef*)String
and so
h("1","2")
res: String = 1,2
However, h(1,2)
error: the result type of an implicit conversion must be more specific than AnyRef
h(1,2)
^
error: the result type of an implicit conversion must be more specific than AnyRef
h(1,2)
^
This is at least in Scala 2.11.1 and 2.11.1. To ask on a workaround.
See Question&Answers more detail:os