#   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

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