| # 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/>. |
| # |
| # This isn't perfect behavior, but it establishes a baseline and will provide |
| # a way to detect behavior changes |
| |
| echo a1 |
| a[0]= a[1]=; recho "${a[@]:-y}" |
| unset a |
| |
| echo a2 |
| a[1]=; recho "${a[@]:-y}" |
| a[1]=; recho "${a[*]:-z}" |
| unset a |
| |
| echo a3 |
| a[0]= a[1]=x; recho "${a[@]:-y}" |
| unset a |
| |
| echo a4 |
| a[0]= a[1]=x; recho ${a[@]:+y} |
| unset a |
| |
| echo p1 |
| set '' '' |
| recho "${@:-y}" |
| |
| shift $# |
| |
| echo p2 |
| set '' x |
| recho "${@:-y}" |
| |
| shift $# |
| |
| echo p3 |
| set '' x |
| recho ${@:+y} |
| |
| # problems with * and null expansions dating back to bash's earliest days |
| A=(''); set -- '' |
| |
| echo "<${A[*]:-X}>" "<${*:-X}>" "<${A:-X}>" "<${A[0]:-X}>" |
| |
| IFS= |
| A=('' ''); set -- '' '' |
| B='' |
| |
| echo "<${A[*]:-X}>" "<${*:-X}>" "<${B:-X}>" "<${B[*]:-X}>" |