diff --git a/Makefile b/Makefile
index a6124fe..75f5667 100644
--- a/Makefile
+++ b/Makefile
@@ -9,11 +9,7 @@ endif
 RPM=cmdarg-$(VERSION)-$(RELEASE).noarch.rpm
 
 ifndef PREFIX
-	PREFIX=/
-endif
-
-ifeq ($(shell uname -o),Cygwin)
-        PREFIX=
+	PREFIX=''
 endif
 
 DISTFILE_DEPS=$(shell find . -type f | grep -Ev '\.git|\./dist/|$(DISTFILE)')
diff --git a/cmdarg.sh b/cmdarg.sh
index 6a45fbc..a0317d6 100644
--- a/cmdarg.sh
+++ b/cmdarg.sh
@@ -46,14 +46,14 @@ function cmdarg
 	if [[ "${1:2:4}" == "[]" ]]; then
 	    declare -p ${key} >/dev/null 2>&1
 	    if [[ $? -ne 0 ]]; then
-		echo 'Array variable cmdarg_'"${key}"' does not exist. Array variables MUST be declared by the user!' >&2
+		echo 'Array variable '"${key}"' does not exist. Array variables MUST be declared by the user!' >&2
 		exit 1
 	    fi
 	    CMDARG_TYPES[$key]=$CMDARG_TYPE_ARRAY
 	elif [[ "${1:2:4}" == "{}" ]]; then
 	    declare -p ${key} >/dev/null 2>&1
 	    if [[ $? -ne 0 ]]; then
-		echo 'Hash variable cmdarg_'"${key}"' does not exist. Hash variables MUST be declared by the user!' >&2
+		echo 'Hash variable '"${key}"' does not exist. Hash variables MUST be declared by the user!' >&2
 		exit 1
 	    fi
 	    CMDARG_TYPES[$key]=$CMDARG_TYPE_HASH
@@ -98,27 +98,28 @@ function cmdarg_info
 
 function cmdarg_describe
 {
+    echo "cmdarg_describe $@" >&2
     local key default
-    key=${CMDARG[$1]}
+    longopt=${CMDARG[$1]}
     opt=$1
-    if [ "${CMDARG_DEFAULT[$key]}" != "" ]; then
-	default="(Default \"${CMDARG_DEFAULT[$key]}\")"
+    if [ "${CMDARG_DEFAULT[$longopt]}" != "" ]; then
+	default="(Default \"${CMDARG_DEFAULT[$longopt]}\")"
     fi
-    case ${CMDARG_TYPES[$key]} in
+    case ${CMDARG_TYPES[$longopt]} in
 	$CMDARG_TYPE_STRING)
-	    echo "-${opt} v : String. ${CMDARG_DESC[$key]} $default"
+	    echo "-${opt} v : String. ${CMDARG_DESC[$opt]} $default"
 	    ;;
 	$CMDARG_TYPE_BOOLEAN)
-	    echo "-${opt} : Boolean. ${CMDARG_DESC[$key]} $default"
+	    echo "-${opt} : Boolean. ${CMDARG_DESC[$opt]} $default"
 	    ;;
 	$CMDARG_TYPE_ARRAY)
-	    echo "-${opt} v[, ...]  : Array. ${CMDARG_DESC[$key]}. Pass this argument multiple times for multiple values. $default"
+	    echo "-${opt} v[, ...]  : Array. ${CMDARG_DESC[$opt]}. Pass this argument multiple times for multiple values. $default"
 	    ;;
 	$CMDARG_TYPE_HASH)
-	    echo "-${opt} k=v{, ..} : Hash. ${CMDARG_DESC[$key]}. Pass this argument multiple times for multiple key/value pairs. $default"
+	    echo "-${opt} k=v{, ..} : Hash. ${CMDARG_DESC[$opt]}. Pass this argument multiple times for multiple key/value pairs. $default"
 	    ;;
 	*)
-	    echo "Unable to return string description for ${key}; unknown type ${CMDARG_TYPES[$key]}" >&2
+	    echo "Unable to return string description for ${key}; unknown type ${CMDARG_TYPES[$opt]}" >&2
 	    exit 1
 	    ;;
     esac
@@ -135,7 +136,6 @@ function cmdarg_usage
     echo
     local key
     if [[ "${!CMDARG_REQUIRED[@]}" != "" ]]; then
-	echo "Required Arguments:"
 	for key in "${CMDARG_REQUIRED[@]}"
 	do
 	    echo "    $(cmdarg_describe $key)"
@@ -143,7 +143,6 @@ function cmdarg_usage
 	echo
     fi
     if [[ "${!CMDARG_OPTIONAL[@]}" != "" ]]; then
-	echo "Optional Arguments:"
 	for key in "${CMDARG_OPTIONAL[@]}"
 	do
 	    echo "    $(cmdarg_describe $key)"
@@ -316,6 +315,23 @@ function cmdarg_dump
     done
 }
 
+function cmdarg_purge
+{
+    arrays="cmdarg_cfg CMDARG CMDARG_REV CMDARG_OPTIONAL CMDARG_REQUIRED"
+    arrays="$arrays CMDARG_DESC CMDARG_DEFAULT CMDARG_VALIDATORS CMDARG_INFO"
+    arrays="$arrays CMDARG_FLAGS CMDARG_TYPES"
+    for arr in $arrays
+    do
+	str='${!'"$arr"'[@]}'
+	for key in $(eval "echo $str")
+	do
+	    str="$arr[$key]"
+	    eval "unset $str"
+	done
+    done
+    CMDARG_GETOPTLIST="h"
+}
+
 if [[ "${_DEFINED_CMDARG}" == "" ]]; then
     export _DEFINED_CMDARG=0
     # Holds the final map of configuration options
diff --git a/tests/test_clean_state.sh b/tests/test_clean_state.sh
new file mode 100644
index 0000000..48297fc
--- /dev/null
+++ b/tests/test_clean_state.sh
@@ -0,0 +1,58 @@
+source $(dirname ${BASH_SOURCE})/../cmdarg.sh
+
+function shunittest_clean_state()
+{
+    # Tests that cmdarg_purge ensures an empty config state
+    function parse1()
+    {
+	cmdarg 'a:' 'a' 'some arg'
+	cmdarg 'b' 'b' 'some arg'
+	cmdarg_parse "$@"
+    }
+
+    function parse2()
+    {
+	cmdarg_purge
+	cmdarg_parse "$@"
+    }
+
+    # This cleans the state from shunit
+    cmdarg_purge
+    parse1 -a 3 -b
+    parse2
+    if [[ "${cmdarg_cfg['a']}" == "" ]]; then
+	return 0
+    else
+	cmdarg_dump
+	return 1
+    fi
+}
+
+function shunittest_clean_state_subshells()
+{
+    # Ensures that, when subsequent cmdarg invocations occur in subshells,
+    # that the initial state is empty even without having called cmdarg_purge
+
+    # This is just here to clean the state from shunit
+    cmdarg_purge
+    function parse1()
+    {
+	cmdarg 'a:' 'a' 'some arg'
+	cmdarg 'b' 'b' 'some arg'
+	cmdarg_parse "$@"
+    }
+
+    function parse2()
+    {
+	cmdarg_parse "$@"
+    }
+
+    (parse1 -a 3 -b)
+    (parse2)
+    if [[ "${cmdarg_cfg['a']}" == "" ]]; then
+	return 0
+    else
+	cmdarg_dump
+	return 1
+    fi
+}
\ No newline at end of file
diff --git a/tests/test_types.sh b/tests/test_types.sh
new file mode 100644
index 0000000..0cd0cba
--- /dev/null
+++ b/tests/test_types.sh
@@ -0,0 +1,74 @@
+source $(dirname ${BASH_SOURCE})/../cmdarg.sh
+
+function shunittest_array_undefined()
+{
+    # Tests that cmdarg and cmdarg_parse return an error when an array
+    # is undefined
+    cmdarg_purge
+    err=$(cmdarg 'a:[]' 'missingarray' 2>&1)
+    if [[ $? -eq 0 ]]; then
+	echo "cmdarg fails to throw an error for undefined array variables"
+    else
+	echo "$err" | grep "Array variable missingarray does not exist" >/dev/null
+	if [[ $? -ne 0 ]]; then
+	    echo "cmdarg does not report errors on stderr for undefined arrays"
+	    echo "$err"
+	    return 1
+	fi
+    fi
+    return 0
+}
+
+function shunittest_array_values
+{
+    cmdarg_purge
+    declare -a array
+    cmdarg 'a:[]' 'array'
+    cmdarg_parse -a a -a b -a c
+    if [[ "${array[@]}" != "a b c" ]]; then
+    	echo "Array does not contain expected arguments"
+    	cmdarg_dump >&2
+    	return 1
+    fi
+    return $?
+}
+
+function shunittest_hash_undefined()
+{
+    # Tests that cmdarg and cmdarg_parse return an error when an array
+    # is undefined
+    cmdarg_purge
+    err=$(cmdarg 'a:{}' 'missingarray' 2>&1)
+    if [[ $? -eq 0 ]]; then
+	echo "cmdarg fails to throw an error for undefined hash variables"
+    else
+	echo "$err" | grep "Hash variable missingarray does not exist" >/dev/null
+	if [[ $? -ne 0 ]]; then
+	    echo "cmdarg does not report errors on stderr for undefined hashes"
+	    echo "$err"
+	    return 1
+	fi
+    fi
+    return 0
+}
+
+function shunittest_hash_values
+{
+    cmdarg_purge
+    declare -A hash
+    cmdarg 'H:{}' 'hash'
+    cmdarg_parse -H a=1 -H b=2 -H c=3
+    base="a=1 b=2 c=3"
+    cmp=""
+    for k in a b c
+    do
+	cmp="$cmp ${k}=${hash[$k]}"
+    done
+    cmp=$(echo "$cmp" | sed s/'^\s*'//)
+    if [[ "$cmp" != "$base" ]]; then
+    	echo "Hash does not contain expected arguments ($cmp vs $base)"
+    	cmdarg_dump >&2
+    	return 1
+    fi
+    return $?
+}
\ No newline at end of file