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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/>.
#
# tests of return value inversion
# placeholder for future expansion
# user subshells (...) did this wrong in bash versions before 2.04
! ( echo hello | grep h >/dev/null 2>&1 ); echo $?
! echo hello | grep h >/dev/null 2>&1 ; echo $?
! true ; echo $?
! false; echo $?
! (false) ; echo $?
! (true); echo $?
! true | false ; echo $?
! false | true ; echo $?
! (true | false) ; echo $?
! (false | true) ; echo $?
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