opt parsing in bash

equal_sep.sh

#!/bin/bash

for i in "$@"
do
case $i in
    -e=*|--extension=*)
    EXTENSION="${i#*=}"
    shift # past argument=value
    ;;
    -s=*|--searchpath=*)
    SEARCHPATH="${i#*=}"
    shift # past argument=value
    ;;
    -l=*|--lib=*)
    LIBPATH="${i#*=}"
    shift # past argument=value
    ;;
    --default)
    DEFAULT=YES
    shift # past argument with no value
    ;;
    *)
          # unknown option
    ;;
esac
done
echo "FILE EXTENSION  = ${EXTENSION}"
echo "SEARCH PATH     = ${SEARCHPATH}"
echo "LIBRARY PATH    = ${LIBPATH}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
    echo "Last line of file specified as non-opt/last argument:"
    tail -1 $1
fi

space_sep.sh

#!/bin/bash

POSITIONAL=()
while [[ $# -gt 0 ]]
do
key="$1"

case $key in
    -e|--extension)
    EXTENSION="$2"
    shift # past argument
    shift # past value
    ;;
    -s|--searchpath)
    SEARCHPATH="$2"
    shift # past argument
    shift # past value
    ;;
    -l|--lib)
    LIBPATH="$2"
    shift # past argument
    shift # past value
    ;;
    --default)
    DEFAULT=YES
    shift # past argument
    ;;
    *)    # unknown option
    POSITIONAL+=("$1") # save it in an array for later
    shift # past argument
    ;;
esac
done
set -- "${POSITIONAL[@]}" # restore positional parameters