#!/bin/bash

# can we see a difference between [] and [[]] for
#     && || < >

echo "$1 $2 $3"

if (( ($1 < $2) && ($2 < $3) ))
then
    echo "three args in order"
else
    echo "three args NOT in order"
fi

# the below seems to work with [[ ]]
#    and gives a syntax error for [ ]

if [[ ( -e $4 ) && ( -d $4) ]]
then
    echo $4 is an existing directory
else
    echo $4 either does not exist and/or is not a dir
fi

argfile=$4

if [[ ( -e $argfile ) && ( -d $argfile) ]]
then
    echo $argfile is an existing directory
else
    echo $argfile either does not exist and/or is not a dir
fi