dnl @ ../doc/m4.texinfo:1441: Origin of test
dnl @ Copyright (C) 2006 Free Software Foundation
dnl @ This file is free software; the Free Software Foundation
dnl @ gives unlimited permission to copy and/or distribute it
dnl @ with or without modifications, as long as this notice
dnl @ is preserved.
define(`f', ``$0':$1')
dnl @result{}
f(f(f(undefine(`f')`hello world')))
dnl @result{}f:f:f:hello world
f(`bye')
dnl @result{}f(bye)