HOME=/usr/xyz
XPATH=/bin:/usr/bin:.

ADDPATH=PATH=~/bin:$XPATH

echo $ADDPATH

unset ADDPATH
: ${ADDPATH:=~/bin:~/bin2:$XPATH}
echo $ADDPATH

unset ADDPATH
: ${ADDPATH:=PATH=~/bin:~/bin2:$XPATH}
echo $ADDPATH

cat << !
~/bin
!

echo "~"

echo ${TPATH:-~}
echo "${TPATH:-~}"
echo "${TPATH:-"~"}"

echo "${XPATH+~}"

recho "\a"
recho "${TPATH:-\a}"

SHELL=~/bash
echo $SHELL

case $SHELL in
~/bash)	echo ok;;
*)	echo bad;;
esac

somevar=
echo "${somevar:-~}"
echo "${somevar:-"~"}"

echo make -k FOO=~/mumble

typeset FOO=~/mumble
echo "$FOO"