That's just documentation tool but the method is actually already statically typed by ruby. I'm not sure why they don't link that in the documenation but I bel

That's just documentation tool but the method is actually already statically typed by ruby. I'm not sure why they don't link that in the documenation but I beleive it is something the RDoc mainer wants to do. def lines: (?string? separator, ?chomp: boolish) -> Array[String] | (?string? separator, ?chomp: boolish) { (String line) -> void } -> self https://github.com/ruby/rbs/blob/master/core/string.rbs https://github.com/ruby/rbs/blob/master/core/string.rbs