What are all the uses of an underscore in Scala?

Question

I\'ve taken a look at the list of surveys taken on scala-lang.org and noticed a curious question: \"Can you name all the uses of “_”?\". Can you? If yes, please do so here.

Answer 1

There is a specific example that "_" be used:

  type StringMatcher = String => (String => Boolean)

  def starts: StringMatcher = (prefix:String) => _ startsWith prefix

may be equal to :

  def starts: StringMatcher = (prefix:String) => (s)=>s startsWith prefix

Applying “_” in some scenarios will automatically convert to “(x$n) => x$n ”