cat script
emp_name="Sid"
emp_id=1234
emp_hobby=""
emp_likes="swimming"
emp_dislikes=""
emp_summary=""
summary=""
for var in emp_name emp_id emp_hobby emp_likes emp_dislikes
do
declare -n namref=$var;
[ "" != "$namref" ] && summary+="${!namref}:$namref,"
done
emp_summary="${summary/%,/}"
echo "emp_summary:${emp_summary}"
./script
emp_summary:emp_name:Sid,emp_id:1234,emp_likes:swimming