yield.rb

def do_something
  puts "Starts"
  text = yield
  puts text
end

do_something do
  next "Now!"
end

do_something do
  return "Oh no!"
end

Starts
Now!
Starts
foo.rb:12:in `block in <main>': unexpected return (LocalJumpError)
	from foo.rb:3:in `do_something'
	from foo.rb:11:in `<main>'