diff --git a/datatype.go b/datatype.go
index bf86e06..31603e7 100644
--- a/datatype.go
+++ b/datatype.go
@@ -5,29 +5,34 @@ import (
 	"time"
 )
 
-type DataType uint
+type DataType uint32
 
 const (
-	TypeNone      DataType = iota
-	TypeInt       DataType = iota
-	TypeMetric    DataType = iota
-	TypeDuration  DataType = iota
-	TypeString    DataType = iota
-	TypeDirectory DataType = iota
-	TypeBool      DataType = iota
-	TypeHex       DataType = iota
+	sizeBitmask DataType = 0xffff
+	typeBitmask DataType = sizeBitmask << 16
 )
 
-func FixedHex(size uint) DataType {
-	return (DataType)(size<<16) | TypeHex
+const (
+	TypeNone      DataType = iota << 16
+	TypeInt       DataType = iota << 16
+	TypeMetric    DataType = iota << 16
+	TypeDuration  DataType = iota << 16
+	TypeString    DataType = iota << 16
+	TypeDirectory DataType = iota << 16
+	TypeBool      DataType = iota << 16
+	TypeHex       DataType = iota << 16
+)
+
+func FixedHex(size uint16) DataType {
+	return TypeHex | DataType(size)
 }
 
 func (dtype DataType) baseType() DataType {
-	return dtype & 0xffff
+	return dtype & typeBitmask
 }
 
-func (dtype DataType) typeAndSize() (DataType, uint) {
-	return (dtype & 0xffff), uint(dtype >> 16)
+func (dtype DataType) typeAndSize() (DataType, int) {
+	return (dtype & typeBitmask), int(dtype & sizeBitmask)
 }
 
 type cValue struct {
diff --git a/parsers.go b/parsers.go
index 1680095..cb72180 100644
--- a/parsers.go
+++ b/parsers.go
@@ -11,7 +11,7 @@ import (
 	"time"
 )
 
-func parseInt(key string, str string, _ uint) (ret cValue) {
+func parseInt(key string, str string, _ int) (ret cValue) {
 	val, err := strconv.ParseInt(str, 10, 64)
 	if err == nil {
 		ret.intval = val
@@ -21,7 +21,7 @@ func parseInt(key string, str string, _ uint) (ret cValue) {
 	return
 }
 
-func parseMetric(key string, str string, _ uint) (ret cValue) {
+func parseMetric(key string, str string, _ int) (ret cValue) {
 	mod := int64(1)
 	str = strings.ToUpper(str)
 	if strings.HasSuffix(str, "K") {
@@ -46,7 +46,7 @@ func parseMetric(key string, str string, _ uint) (ret cValue) {
 	return
 }
 
-func parseDuration(key string, str string, _ uint) (ret cValue) {
+func parseDuration(key string, str string, _ int) (ret cValue) {
 	val, err := time.ParseDuration(str)
 	if err == nil {
 		ret.durval = val
@@ -56,7 +56,7 @@ func parseDuration(key string, str string, _ uint) (ret cValue) {
 	return
 }
 
-func parseBool(key string, str string, _ uint) (ret cValue) {
+func parseBool(key string, str string, _ int) (ret cValue) {
 	val, err := strconv.ParseBool(str)
 	if err == nil {
 		ret.boolval = val
@@ -66,9 +66,9 @@ func parseBool(key string, str string, _ uint) (ret cValue) {
 	return
 }
 
-func parseHex(key string, str string, size uint) (ret cValue) {
+func parseHex(key string, str string, size int) (ret cValue) {
 	val, err := hex.DecodeString(str)
-	if err == nil && (size == 0 || size == uint(len(val))) {
+	if err == nil && (size == 0 || size == len(val)) {
 		ret.binval = val
 	} else {
 		if size == 0 {
@@ -80,7 +80,7 @@ func parseHex(key string, str string, size uint) (ret cValue) {
 	return
 }
 
-func parseDirectory(_ string, str string, _ uint) (ret cValue) {
+func parseDirectory(_ string, str string, _ int) (ret cValue) {
 	wd, err := os.Getwd()
 	if err == nil {
 		if path.IsAbs(str) {
@@ -94,7 +94,7 @@ func parseDirectory(_ string, str string, _ uint) (ret cValue) {
 	return
 }
 
-func parseString(_ string, str string, _ uint) (ret cValue) {
+func parseString(_ string, str string, _ int) (ret cValue) {
 	ret.strval = str
 	return
 }
diff --git a/typeinfo.go b/typeinfo.go
index 0648ce8..3154934 100644
--- a/typeinfo.go
+++ b/typeinfo.go
@@ -1,7 +1,7 @@
 package envconf
 
 type dataTypeInfo struct {
-	parser func(string, string, uint) cValue
+	parser func(string, string, int) cValue
 	name   string
 }