dnl @ ../doc/m4.texi:4194: Origin of test
dnl @ expected status: 0
dnl @ extra options: 
dnl @ Copyright (C) 2006, 2007, 2008, 2009 Free Software
dnl @ Foundation, Inc.
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.
dnl(`args are ignored, but side effects occur',
define(`foo', `like this')) while this text is ignored: undefine(`foo')
dnl @error{}m4:stdin:1: Warning: excess arguments to builtin `dnl' ignored
See how `foo' was defined, foo?
dnl @result{}See how foo was defined, like this?