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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/>.
#
set -o posix
fn() { foo=abc : ; typeset +x foo; printenv|grep ^foo=; }
fn
unset -v foo
unset -f fn
func1() {
var=1
var=2 : # or 'var=2 return', or another special builtin
unset -v var
echo $FUNCNAME: var = $var
}
func2() {
func1
unset -v var # bug: fails silently
}
func1
echo ${var+"BUG: still set 1"}
unset var
func2
echo ${var+"BUG: still set 2"}
unset -v var
unset -f func1 func2
fn() { foo=abc : ; typeset +x foo; echo -n 'inside: ' ; declare -p foo; }
fn
echo outside:
declare -p foo
unset -v foo
unset -f fn
func()
{
var=value declare -x var
echo -n 'inside: ' ; declare -p var
}
var=one
func
echo -n 'outside: ' ; declare -p var
unset -v var
unset -f func
# this will probably change behavior; export shouldn't behave like this when
# not in posix mode and the sequencing is probably wrong in posix mode. since
# export is a special builtin, the variable assignment should modify the
# local variable, as if a standalone assignment statement had been executed
# (posix modifying "the current execution environment") leaving the global
# variable unchanged. all shells, including bash, modify the local variable;
# bash was the only one that propagates the value out to the calling
# environment, but no longer does so.
func()
{
local var=inside
var=value export var
echo -n 'inside: ' ; declare -p var
}
var=outside
func
echo -n 'outside: ' ; declare -p var
unset -v var
unset -f func
func()
{
local var=local
var=inside :
echo -n 'inside: ' ; declare -p var
}
var=outside
func
echo -n 'outside: ' ; declare -p var
unset -v var
unset -f func
func()
{
echo -n 'inside func: ' ; echo "var=${var-<unset>}"
}
unset -v var
var=one :
echo -n 'outside 1.0: ' ; echo "var=${var-<unset>}"
unset -v var
var=one eval ':'
echo -n 'outside 1.1: ' ; echo "var=${var-<unset>}"
unset -v var
var=two func
echo -n 'outside 2.0: ' ; echo "var=${var-<unset>}"
var=global
var=two func
echo -n 'outside 2.1: ' ; echo "var=${var-<unset>}"
unset -v var
unset -f func
func1()
{
var=value export var
echo -n 'inside func1: ' ; echo "var=${var-<unset>}"
}
var=outside
func1
echo -n 'outside 3.0: ' ; echo "var=${var-<unset>}"
unset -v var
unset -f func1
# operations inside a function on temporary variables do not propagate
func1()
{
export var
echo -n 'inside func1: ' ; echo "var=${var-<unset>}"
}
var=outside
var=func func1
echo -n 'outside 3.5: ' ; echo "var=${var-<unset>}"
unset -v var
unset -f func1
func2()
{
local var=local
var=global :
echo -n 'inside func2: ' ; echo "var=${var-<unset>}"
}
var=outside
func2
echo -n 'outside 4.0: ' ; echo "var=${var-<unset>}"
unset -v var
unset -f fecho foo bar
fecho() {
echo $var
}
foo() {
local var="foo: bye bye"
var="foo: hello world" fecho
}
bar() {
var="bar: hello world" fecho
}
var=global
var=outside foo
echo after foo: var=$var
var=global
var=outside bar
echo after bar: var=$var
unset -v var
|
