Hi,
below is a piece of code written by my predecessor at work.
I'm kind of a newbie and am trying to figure out all the regular expressions in this piece of code.
It is really a tough time for me to figure out all the regular expressions.

Please shed some light on the regular expressions in this code

ssh_list() {
typeset userAtHost="$1"
typeset dir="${2-.}"
typeset wild="${3-*}"

info "SSH list: $userAtHost $src $dst"

if [ "$REGION" != prod ] ;then
userAtHost=$LOGNAME@localhost
fi

# Save, disable, and restore the verbose flag - any
# verbose output would look like errors.
typeset verbose="$(set -o |sed -n 's/^verbose *//p')"
set +v
typeset msgs="$(sftp $userAtHost 2>&1 <<EOF
cd $dir
ls
EOF)"
if [ "$verbose" = on ] ;then
set -v
fi

# Strip the "Connecting to host..." line, prompts, blank lines
# and login banners. What's left should only be error messages.
typeset errs="$(echo "$msgs" |
sed -e '/^Connecting to .*\.\.\.$/d' \
-e 's/sftp > //g' \
-e '/^[ ]*$/d' \
-e '/^#/d' \
-e '/^[-dDlbcps][-rwxsStTlL]\{9\}+\{0,1\} /d')"

if [ "$errs" != "" ] ;then
error "$errs"
return 1
fi

echo "$msgs" |
while read line
do
case "$line" in -*\ $wild)
echo ${line##* }
;;esac
done

return 0
}

I'd like some explanation of these lines.... gurus please shed some light.

Thank you for your time.
Ram