diff --git a/headers.js b/headers.js
index 69f4439..e4d828f 100644
--- a/headers.js
+++ b/headers.js
@@ -2,15 +2,15 @@ var ZEROS = '0000000000000000000';
 var ZERO_OFFSET = '0'.charCodeAt(0);
 var USTAR = 'ustar00';
 
-function clamp(index, len, defaultValue) {
-  if (typeof index !== 'number') return defaultValue;
-  index = ~~index;  // Coerce to integer.
-  if (index >= len) return len;
-  if (index >= 0) return index;
-  index += len;
-  if (index >= 0) return index;
-  return 0;
-}
+var clamp = function(index, len, defaultValue) {
+	if (typeof index !== 'number') return defaultValue;
+	index = ~~index;  // Coerce to integer.
+	if (index >= len) return len;
+	if (index >= 0) return index;
+	index += len;
+	if (index >= 0) return index;
+	return 0;
+};
 
 var toType = function(flag) {
 	switch (flag) {
diff --git a/test/extract.js b/test/extract.js
index f40d060..6880cae 100644
--- a/test/extract.js
+++ b/test/extract.js
@@ -4,15 +4,15 @@ var fixtures = require('./fixtures');
 var concat = require('concat-stream');
 var fs = require('fs');
 
-function clamp(index, len, defaultValue) {
-  if (typeof index !== 'number') return defaultValue;
-  index = ~~index;  // Coerce to integer.
-  if (index >= len) return len;
-  if (index >= 0) return index;
-  index += len;
-  if (index >= 0) return index;
-  return 0;
-}
+var clamp = function(index, len, defaultValue) {
+	if (typeof index !== 'number') return defaultValue;
+	index = ~~index;  // Coerce to integer.
+	if (index >= len) return len;
+	if (index >= 0) return index;
+	index += len;
+	if (index >= 0) return index;
+	return 0;
+};
 
 test('one-file', function(t) {
 	t.plan(3);