1 files changed, 13 insertions, 2 deletions
diff --git a/index.js b/index.js
index 71d93d9..423295b 100644
--- a/index.js
+++ b/index.js
@@ -1,5 +1,9 @@
 
-module.exports = basic = {}
+var basic = {}
+
+if (! ('window' in this)) {
+  module.exports = basic
+}
 
 // Handle bases up to base 36
 basic.abedecary = "0123456789abcdefghijklmnopqrstuvwxyz"
@@ -38,10 +42,17 @@ basic.toNumber = function (s, b) {
 	if (! basic.validate(s, b)) {
 	  return NaN
 	}
-  var n = 0
+  var n = 0, is_negative = false
+	if (s.indexOf("-") == 0) {
+	  is_negative = true
+		s = s.substr(1)
+	}
 	for (var i = 0, len = s.length; i < len; i++) {
 	  n += basic.abedecary.indexOf(s[len-1-i]) * Math.pow(b, i)
 	}
+	if (is_negative) {
+	  n *= -1
+	}
 	return n
 }