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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/>.
#
pat1='str'
pat2='[^;]'
pat3='[[:alnum:]_]'
pat4='[[:alnum:]][[fu]b'
pat5='?tr'
pat6='?tr\'
pat7='[[:alnum:]]_'
pat8='*tr'
declare z="start"
declare NUM=1000
#----------------------------------
# create a long string with ';'
#----------------------------------
for ((i=0; i<$NUM; i++)); do
z="$z;string$i"
done
#z="$z;string;foo"
#------------------------------
# delete everything except ';'
#------------------------------
# try different patterns here
x="${z//$pat1}"
echo $x
x="${z//$pat2}"
echo $x
x="${z//$pat3}"
echo $x
x="${z//$pat4}"
echo $x
x="${z//$pat5}"
echo $x
x="${z//$pat6}"
echo $x
x="${z//$pat7}"
echo $x
x="${z//$pat8}"
echo $x
declare z="start"
declare NUM=1000
#----------------------------------
# create a long string with ';'
#----------------------------------
for ((i=0; i<$NUM; i++)); do
z="$z;string$i"
done
#z="$z;string;foo"
#------------------------------
# delete everything except ';'
#------------------------------
# try different patterns here
x="${z//[^;]}"
echo $x
x="${z/#[^;][^;]}"
echo $x
x="${z/%[^;][^;]}"
echo $x
export LANG=C LC_ALL=C LC_CTYPE=C
# try different patterns here
x="${z//$pat1}"
echo $x
x="${z//$pat2}"
echo $x
x="${z//$pat3}"
echo $x
x="${z//$pat4}"
echo $x
x="${z//$pat5}"
echo $x
x="${z//$pat6}"
echo $x
x="${z//$pat7}"
echo $x
x="${z//$pat8}"
echo $x
# try different patterns here
x="${z//[^;]}"
echo $x
x="${z/#[^;][^;]}"
echo $x
x="${z/%[^;][^;]}"
echo $x
# post-bash-4.3 changes to make pattern replacement honor nocasematch variable
unset string
string=abcd
shopt -s nocasematch
echo ${string//A/z}
echo ${string//BC/x}
echo ${string//[BC]/x}
echo ${string//[bC]/x}
echo ${string//?/z}
LC_ALL=C
echo ${string//A/z}
echo ${string//BC/x}
echo ${string//[BC]/x}
echo ${string//[bC]/x}
echo ${string//?/z}
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