1 files changed, 38 insertions, 18 deletions

diff --git a/index.js b/index.js
index 6218073..71d93d9 100644
--- a/index.js
+++ b/index.js
@@ -6,32 +6,41 @@ basic.abedecary = "0123456789abcdefghijklmnopqrstuvwxyz"
 
 // Validate that a string s represents a number in base b
 basic.validate = function (s, b) {
-  return (base.validate_base(b) && base.validate_digits(s, b))
+  return (basic.validate_base(b) && basic.validate_digits(s, b))
 }
 
 // Validate that a string does not contain numerals
 // foreign to a particular base.
 basic.validate_digits = function(s, b) {
-  var A = basic.abedecary.substr(0, b)
-	var re = new RegExp ( "[^" + A + "]" )
-	return !! re.match(s)
+  var A = basic.abedecary.substr(0, Math.abs(b))
+	if (b > 0) {
+	  A = "-" + A
+  }
+	var re = new RegExp ( "[^" + A + "]", "g" )
+	return ! re.test(s)
 }
 
 // Validate that a base is valid.
 basic.validate_base = function(b){
-	return (b !== 0 && b !== 1 && b !== -1 && (Math.abs(b) % 2) === 0)
+	return (
+	   ! isNaN(b)
+	&& b !== 0
+	&& b !== 1
+	&& b !== -1
+	&& (Math.abs(b) % 1) === 0
+	&& Math.abs(b) <= 36
+	)
 }
 
 // Convert a string s representing a number in base b
 // to an integer.  Assumes s is big-endian.
 basic.toNumber = function (s, b) {
-	if (! basic.validate(s,b)) {
+	if (! basic.validate(s, b)) {
 	  return NaN
 	}
   var n = 0
-	s = s.reverse()
 	for (var i = 0, len = s.length; i < len; i++) {
-	  n += parseInt(s[i]) * Math.pow(b, i)
+	  n += basic.abedecary.indexOf(s[len-1-i]) * Math.pow(b, i)
 	}
 	return n
 }
@@ -42,23 +51,34 @@ basic.toString = function (n, b) {
 	if (! basic.validate_base(b)) {
 	  throw new Error ("invalid base")
 	}
+	if (n === 0) {
+	  return "0"
+	}
+	var is_negative = n < 0
+	if (is_negative && b > 0) {
+	  n = Math.abs(n)
+	}
 	var s = ""
-	var dividend, residual
 	while (n) {
-	  remainder = basic.mod(n, b)
-    n = Math.floor(n/b)
-		if (remainder) {
+	  var remainder = n % b
+    n = basic.floor(n / b)
+		if (remainder < 0) {
 		  n += 1
+			remainder -= b
 		}
-		s += basic.abedecary[n]
+		s = basic.abedecary[remainder] + s
+	}
+	if (is_negative && b > 0) {
+	  s = "-" + s
 	}
 	return s
 }
 
-// Compute the residual of N mod M
-// Handle negative N and M correctly
-basic.mod = function (n,m){
-	m = Math.abs(m)
-  return n-(m * Math.floor(n/m))
+// Remove the mantissa from a number, handling negative numbers
+basic.floor = function (n){
+  if (n >= 0) {
+	  return Math.floor(n)
+  }
+	return -1 * Math.floor(-n)
 }