dnl @ ../doc/m4.texi:6364: 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.
define(`_counter', `-1')dnl
define(`counter', `ifelse(`$#', `0', `define(`_$0', incr(_$0))_$0`'',
`define(`_$0', eval(`$1-1'))')')
dnl @result{}
counter counter counter
dnl @result{}0 1 2
counter(`42')
dnl @result{}
counter counter
dnl @result{}42 43
counter()counter
dnl @result{}0