# File lib/rake.rb, line 514
514:     def invoke_prerequisites(task_args, invocation_chain)
515:       @prerequisites.each { |n|
516:         prereq = application[n, @scope]
517:         prereq_args = task_args.new_scope(prereq.arg_names)
518:         prereq.invoke_with_call_chain(prereq_args, invocation_chain)
519:       }
520:     end