Paren-less methods

A paren-less method is a method that doesn’t take parameters (a nullary method) and that is declared without parentheses:

def foo: Int = 1

Trying to call is with parentheses will fail:

foo()
// error: Int does not take parameters
// foo()
// ^^^^^

An interesting property of paren-less methods is that they can be overridden (or implemented, if abstract) by vals.