Question

I have been using :_* to convert Seq[String] to String* and I realized that I do not understand how this works under the hood.

Is there a simple way to think about this?

Answer 1

Under the hood, String* is passed as a Seq[String]. It’s all just syntactic sugar:

def blah(ss: String*) = {...}
blah("Hi","there")

is turned into

def blah(ss: Seq[String]) = {...}
blah(Seq("Hi", "there"))

and :_* just means “hold the sugar, I’ve already got what you need–a Seq!”