set -- ''; 

recho "${@}" x
recho "${@:1}" x

set -- "${@:1}"
echo "$#" 

set  -- '' ''

recho "${@:1}" x 
recho "${@:1:1}" x 

typeset -a A	# ksh93 needs this
A=('' '')
recho "${A[@]:0}" x 

recho "${A[@]:0:1}" x

recho "${A[@]:1}" x 

set -- ''

recho "${@/foo/bar}"
recho "${@^^[abcde]}"

A=( '' )

recho "${A[@]/foo/bar}"
recho "${A[@],,[abcde]}"