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# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# new framework for parameter transformations, post bash-4.3
printf "<%s>" "${x@Q}" ; echo
printf "<%s>" "${x@E}" ; echo
printf "<%s>" "${x@P}" ; echo
printf "<%s>" "${x@A}" ; echo
x="ab 'cd' ef"
printf "<%s> " "${x@Q}" ; echo
# this needs to be run in a subshell because invalid transformation operators
# are now treated as substitution errors, fatal in non-interactive shells
${THIS_SH} -c 'x=abcdef ; printf "<%s>" "${x@C}"' bash
# if unquoted, normal word splitting happens
set -- ab 'cd ef' '' gh
printf "<%s> " "${@@Q}" ; echo
printf "<%s> " "${*@Q}" ; echo
printf "<%s> " ${@@Q} ; echo
printf "<%s> " ${*@Q} ; echo
y[0]=4
y[1]='ab cd'
printf "<%s> " "${y[1]@Q}" ; echo
printf "<%s> " "${y[@]@Q}" ; echo # mksh doesn't like @ or * or arrays subscripted with them
printf "<%s> " "${z@Q}" ; echo # empty string?
recho ${z@Q} # this disappears
#
D=' \t\n'
printf "<%s>" "${D@E}" ; echo
printf "<%s>" "${D@Q}" ; echo
E=$' \t\n'
printf "<%s>" "${E@E}" ; echo
printf "<%s>" "${E@Q}" ; echo
v=$'\1\1'
printf '%q\n' "${v@E}"
unset -v v
declare x
declare -r x="ab 'cd' ef"
printf "%s" "${x@A}" ; echo
set -- ab 'cd ef' '' gh
printf "%s " "${@@A}" ; echo
A=( "$@" )
printf "%s " "${A[@]@A}" ; echo
B=()
printf "%s " "${B[@]@A}" ; echo
unset A
declare -A A
A=( [one]=1 [two]='b c' [three]='' [four]=de )
printf "%s " "${A[@]@A}" ; echo
unset X
declare X
declare -r X="ab 'cd' ef"
printf "%s" "${X@a}" ; echo
set -- 1 2 3 4
unset A
A=( "$@" )
printf "%s " "${A@a}" ; echo
unset A
declare -A A
A=( [one]=1 [two]='b c' [three]='' [four]=de )
printf "%s " "${A@a}" ; echo
declare -ir Y=0
printf "%s" "${Y@a}" ; echo
# make sure we still handle ${#@} and ${@} as posix requires
set -- a b c d e
echo ${@}
echo ${#@}
echo a${#@}b
# new feature in bash-5.0: display attributes of even unset variables
unset -v foo
declare -i foo
echo ${foo@a}
declare -p foo
unset foo
declare -A foo
echo ${foo@a}
declare -p foo
unset -v foo
foo=lower
echo ${foo@U}
echo ${foo@u}
# framework for testing prompt expansions using @P transformation
cd /tmp
HOST=host
SHELL_LEVEL=2
HOME=$PWD
NPS1='\[\]${HOST}($SHELL_LEVEL)[\v]\$ '
recho "${NPS1@P}"
NPS1='\[\]\W\$\040'
recho "${NPS1@P}"
NPS1='\[\001\][\j]\w\$\040'
recho "${NPS1@P}"
NPS1='\[\a\][\j:\!]\w\\\$\040'
set -o emacs
recho "${NPS1@P}"
set +o emacs
cd /
# no longer abbreviate as ~
NPS1='\W \s\$\040'
recho "${NPS1@P}"
set -o posix
NPS1='!\n\W \s\$\040'
recho "${NPS1@P}"
cd $OLDPWD
# this must be last, fatal error
V=42
echo ${V@} # error
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