diff --git a/strftime.js b/strftime.js
index 4b50c80..8b902ec 100644
--- a/strftime.js
+++ b/strftime.js
@@ -9,358 +9,413 @@
 // http://sjs.mit-license.org
 //
 
-;(function() {
+;
+(function () {
+    //// Where to export the API
+    var namespace;
 
-  //// Where to export the API
-  var namespace;
-
-  // CommonJS / Node module
-  if (typeof module !== 'undefined') {
-    namespace = module.exports = strftime;
-  }
-
-  // Browsers and other environments
-  else {
-    // Get the global object. Works in ES3, ES5, and ES5 strict mode.
-    namespace = (function(){ return this || (1,eval)('this') }());
-  }
-
-  function words(s) { return (s || '').split(' '); }
-
-  var DefaultLocale =
-  { days: words('Sunday Monday Tuesday Wednesday Thursday Friday Saturday')
-  , shortDays: words('Sun Mon Tue Wed Thu Fri Sat')
-  , months: words('January February March April May June July August September October November December')
-  , shortMonths: words('Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec')
-  , AM: 'AM'
-  , PM: 'PM'
-  , am: 'am'
-  , pm: 'pm'
-  };
-
-  namespace.strftime = strftime;
-  function strftime(fmt, d, locale) {
-    return _strftime(fmt, d, locale);
-  }
-
-  // locale is optional
-  namespace.strftimeTZ = strftime.strftimeTZ = strftimeTZ;
-  function strftimeTZ(fmt, d, locale, timezone) {
-    if ((typeof locale == 'number' || typeof locale == 'string') && timezone == null) {
-      timezone = locale;
-      locale = undefined;
+    try {
+        // CommonJS / Node module
+        namespace = module.exports = strftime;
+    } catch (error) {
+        // Browsers and other environments
+        // Get the global object. Works in ES3, ES5, and ES5 strict mode.
+        namespace = new Function('return this')();
     }
-    return _strftime(fmt, d, locale, { timezone: timezone });
-  }
 
-  namespace.strftimeUTC = strftime.strftimeUTC = strftimeUTC;
-  function strftimeUTC(fmt, d, locale) {
-    return _strftime(fmt, d, locale, { utc: true });
-  }
-
-  namespace.localizedStrftime = strftime.localizedStrftime = localizedStrftime;
-  function localizedStrftime(locale) {
-    return function(fmt, d, options) {
-      return strftime(fmt, d, locale, options);
+    var DefaultLocale = {
+        days: 'Sunday Monday Tuesday Wednesday Thursday Friday Saturday'.split(' '),
+        shortDays: 'Sun Mon Tue Wed Thu Fri Sat'.split(' '),
+        months: 'January February March April May June July August September October November December'.split(' '),
+        shortMonths: 'Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec'.split(' '),
+        AM: 'AM',
+        PM: 'PM',
+        am: 'am',
+        pm: 'pm'
     };
-  }
 
-  // d, locale, and options are optional, but you can't leave
-  // holes in the argument list. If you pass options you have to pass
-  // in all the preceding args as well.
-  //
-  // options:
-  //   - locale   [object] an object with the same structure as DefaultLocale
-  //   - timezone [number] timezone offset in minutes from GMT
-  function _strftime(fmt, d, locale, options) {
-    options = options || {};
+    var RequiredDateMethods = [
+        'getTime',
+        'getTimezoneOffset',
+        'getDay',
+        'getDate',
+        'getMonth',
+        'getFullYear',
+        'getYear',
+        'getHours',
+        'getMinutes',
+        'getSeconds'
+    ];
 
-    // d and locale are optional so check if d is really the locale
-    if (d && !quacksLikeDate(d)) {
-      locale = d;
-      d = undefined;
-    }
-    d = d || new Date();
-
-    locale = locale || DefaultLocale;
-    locale.formats = locale.formats || {};
-
-    // Hang on to this Unix timestamp because we might mess with it directly below.
-    var timestamp = d.getTime();
-
-    var tz = options.timezone;
-    var tzType = typeof tz;
-
-    if (options.utc || tzType == 'number' || tzType == 'string') {
-      d = dateToUTC(d);
+    function strftime(fmt, d, locale) {
+        return _strftime(fmt, d, locale);
     }
 
-    if (tz) {
-      // ISO 8601 format timezone string, [-+]HHMM
-      //
-      // Convert to the number of minutes and it'll be applied to the date below.
-      if (tzType == 'string') {
-        var sign = tz[0] == '-' ? -1 : 1;
-        var hours = parseInt(tz.slice(1, 3), 10);
-        var mins = parseInt(tz.slice(3, 5), 10);
-        tz = sign * (60 * hours) + mins;
-      }
+    function strfTimeTZ(fmt, d, locale, timezone) {
+        var _locale = locale;
+        var _timezone = timezone;
 
-      if (tzType) {
-        d = new Date(d.getTime() + (tz * 60000));
-      }
-    }
-
-    // Most of the specifiers supported by C's strftime, and some from Ruby.
-    // Some other syntax extensions from Ruby are supported: %-, %_, and %0
-    // to pad with nothing, space, or zero (respectively).
-    return fmt.replace(/%([-_0]?.)/g, function(_, c) {
-      var mod, padding;
-
-      if (c.length == 2) {
-        mod = c[0];
-        // omit padding
-        if (mod == '-') {
-          padding = '';
+        if ((typeof locale === 'number' || typeof locale === 'string') && timezone == null) {
+            _timezone = locale;
+            _locale = undefined;
         }
-        // pad with space
-        else if (mod == '_') {
-          padding = ' ';
+
+        return _strftime(fmt, d, _locale, {
+            timezone: _timezone
+        });
+    }
+
+    function strftimeUTC(fmt, d, locale) {
+        return _strftime(fmt, d, locale, {
+            utc: true
+        });
+    }
+
+    function localizedStrftime(locale) {
+        return function (fmt, d, options) {
+            return _strftime(fmt, d, locale, options);
+        };
+    }
+
+    // d, locale, and options are optional, but you can't leave
+    // holes in the argument list. If you pass options you have to pass
+    // in all the preceding args as well.
+    //
+    // options:
+    //   - locale   [object] an object with the same structure as DefaultLocale
+    //   - timezone [number] timezone offset in minutes from GMT
+    function _strftime(format, d, locale, options) {
+        var _options = options || {};
+        var _locale = locale;
+        var _d = d;
+
+        // d and locale are optional so check if d is really the locale
+        if (_d && !quacksLikeDate(_d)) {
+            _locale = _d;
+            _d = undefined;
         }
-        // pad with zero
-        else if (mod == '0') {
-          padding = '0';
+
+        _d = _d || new Date();
+
+        _locale = _locale || DefaultLocale;
+        _locale.formats = _locale.formats || {};
+
+        // Hang on to this Unix timestamp because we might mess with it directly below.
+        var timestamp = _d.getTime();
+        var tz = _options.timezone;
+        var tzType = typeof tz;
+
+        if (_options.utc || tzType === 'number' || tzType === 'string') {
+            _d = dateToUTC(_d);
         }
-        else {
-          // unrecognized, return the format
-          return _;
+
+        if (tz) {
+            // ISO 8601 format timezone string, [-+]HHMM
+            // Convert to the number of minutes and it'll be applied to the date below.
+            if (tzType === 'string') {
+                var sign = tz[0] === '-' ? -1 : 1;
+                var hours = parseInt(tz.slice(1, 3), 10);
+                var mins = parseInt(tz.slice(3, 5), 10);
+
+                tz = sign * (60 * hours) + mins;
+            }
+
+            _d = new Date(_d.getTime() + (tz * 60000));
         }
-        c = c[1];
-      }
 
-      switch (c) {
+        // Most of the specifiers supported by C's strftime, and some from Ruby.
+        // Some other syntax extensions from Ruby are supported: %-, %_, and %0
+        // to pad with nothing, space, or zero (respectively).
+        return format.replace(/%([-_0]?.)/g, function (_, c) {
+            var padding;
+            var _c = c;
 
-        // Examples for new Date(0) in GMT
+            if (_c.length === 2) {
+                switch (_c[0]) {
+                    // omit padding
+                    case '-':
+                        padding = '';
+                        break;
 
-        // 'Thursday'
-        case 'A': return locale.days[d.getDay()];
+                    // pad with space
+                    case '_':
+                        padding = ' ';
+                        break;
 
-        // 'Thu'
-        case 'a': return locale.shortDays[d.getDay()];
+                    // pad with zero
+                    case '0':
+                        padding = '0';
+                        break;
 
-        // 'January'
-        case 'B': return locale.months[d.getMonth()];
+                    // unrecognized, return the format
+                    default:
+                        return _;
+                }
 
-        // 'Jan'
-        case 'b': return locale.shortMonths[d.getMonth()];
+                _c = _c[1];
+            }
 
-        // '19'
-        case 'C': return pad(Math.floor(d.getFullYear() / 100), padding);
+            switch (_c) {
+                // Examples for new Date(0) in GMT
 
-        // '01/01/70'
-        case 'D': return _strftime(locale.formats.D || '%m/%d/%y', d, locale);
+                // 'Thursday'
+                case 'A':
+                    return _locale.days[_d.getDay()];
 
-        // '01'
-        case 'd': return pad(d.getDate(), padding);
+                // 'Thu'
+                case 'a':
+                    return _locale.shortDays[_d.getDay()];
 
-        // '01'
-        case 'e': return d.getDate();
+                // 'January'
+                case 'B':
+                    return _locale.months[_d.getMonth()];
 
-        // '1970-01-01'
-        case 'F': return _strftime(locale.formats.F || '%Y-%m-%d', d, locale);
+                // 'Jan'
+                case 'b':
+                    return _locale.shortMonths[_d.getMonth()];
 
-        // '00'
-        case 'H': return pad(d.getHours(), padding);
+                // '19'
+                case 'C':
+                    return pad(Math.floor(_d.getFullYear() / 100), padding);
 
-        // 'Jan'
-        case 'h': return locale.shortMonths[d.getMonth()];
+                // '01/01/70'
+                case 'D':
+                    return _strftime(_locale.formats.D || '%m/%d/%y', _d, _locale);
 
-        // '12'
-        case 'I': return pad(hours12(d), padding);
+                // '01'
+                case 'd':
+                    return pad(_d.getDate(), padding);
 
-        // '000'
-        case 'j':
-          var y = new Date(d.getFullYear(), 0, 1);
-          var day = Math.ceil((d.getTime() - y.getTime()) / (1000 * 60 * 60 * 24));
-          return pad(day, 3);
+                // '01'
+                case 'e':
+                    return _d.getDate();
 
-        // ' 0'
-        case 'k': return pad(d.getHours(), padding == null ? ' ' : padding);
+                // '1970-01-01'
+                case 'F':
+                    return _strftime(_locale.formats.F || '%Y-%m-%d', _d, _locale);
 
-        // '000'
-        case 'L': return pad(Math.floor(timestamp % 1000), 3);
+                // '00'
+                case 'H':
+                    return pad(_d.getHours(), padding);
 
-        // '12'
-        case 'l': return pad(hours12(d), padding == null ? ' ' : padding);
+                // 'Jan'
+                case 'h':
+                    return _locale.shortMonths[_d.getMonth()];
 
-        // '00'
-        case 'M': return pad(d.getMinutes(), padding);
+                // '12'
+                case 'I':
+                    return pad(hours12(_d), padding);
 
-        // '01'
-        case 'm': return pad(d.getMonth() + 1, padding);
+                // '000'
+                case 'j':
+                    var y = new Date(_d.getFullYear(), 0, 1);
+                    var day = Math.ceil((_d.getTime() - y.getTime()) / (1000 * 60 * 60 * 24));
+                    return pad(day, 3);
 
-        // '\n'
-        case 'n': return '\n';
+                // ' 0'
+                case 'k':
+                    return pad(_d.getHours(), padding == null ? ' ' : padding);
 
-        // '1st'
-        case 'o': return String(d.getDate()) + ordinal(d.getDate());
+                // '000'
+                case 'L':
+                    return pad(Math.floor(timestamp % 1000), 3);
 
-        // 'am'
-        case 'P': return d.getHours() < 12 ? locale.am : locale.pm;
+                // '12'
+                case 'l':
+                    return pad(hours12(_d), padding == null ? ' ' : padding);
 
-        // 'AM'
-        case 'p': return d.getHours() < 12 ? locale.AM : locale.PM;
+                // '00'
+                case 'M':
+                    return pad(_d.getMinutes(), padding);
 
-        // '00:00'
-        case 'R': return _strftime(locale.formats.R || '%H:%M', d, locale);
+                // '01'
+                case 'm':
+                    return pad(_d.getMonth() + 1, padding);
 
-        // '12:00:00 AM'
-        case 'r': return _strftime(locale.formats.r || '%I:%M:%S %p', d, locale);
+                // '\n'
+                case 'n':
+                    return '\n';
 
-        // '00'
-        case 'S': return pad(d.getSeconds(), padding);
+                // '1st'
+                case 'o':
+                    return String(_d.getDate()) + ordinal(_d.getDate());
 
-        // '0'
-        case 's': return Math.floor(timestamp / 1000);
+                // 'am'
+                case 'P':
+                    return _d.getHours() < 12 ? _locale.am : _locale.pm;
 
-        // '00:00:00'
-        case 'T': return _strftime(locale.formats.T || '%H:%M:%S', d, locale);
+                // 'AM'
+                case 'p':
+                    return _d.getHours() < 12 ? _locale.AM : _locale.PM;
 
-        // '\t'
-        case 't': return '\t';
+                // '00:00'
+                case 'R':
+                    return _strftime(_locale.formats.R || '%H:%M', _d, _locale);
 
-        // '00'
-        case 'U': return pad(weekNumber(d, 'sunday'), padding);
+                // '12:00:00 AM'
+                case 'r':
+                    return _strftime(_locale.formats.r || '%I:%M:%S %p', _d, _locale);
 
-        // '4'
-        case 'u':
-          var day = d.getDay();
-          return day == 0 ? 7 : day; // 1 - 7, Monday is first day of the week
+                // '00'
+                case 'S':
+                    return pad(_d.getSeconds(), padding);
 
-        // '1-Jan-1970'
-        case 'v': return _strftime(locale.formats.v || '%e-%b-%Y', d, locale);
+                // '0'
+                case 's':
+                    return Math.floor(timestamp / 1000);
 
-        // '00'
-        case 'W': return pad(weekNumber(d, 'monday'), padding);
+                // '00:00:00'
+                case 'T':
+                    return _strftime(_locale.formats.T || '%H:%M:%S', _d, _locale);
 
-        // '4'
-        case 'w': return d.getDay(); // 0 - 6, Sunday is first day of the week
+                // '\t'
+                case 't':
+                    return '\t';
 
-        // '1970'
-        case 'Y': return d.getFullYear();
+                // '00'
+                case 'U':
+                    return pad(weekNumber(_d, 'sunday'), padding);
 
-        // '70'
-        case 'y':
-          var y = String(d.getFullYear());
-          return y.slice(y.length - 2);
+                // '4'
+                case 'u':
+                    var day = _d.getDay();
+                    return day === 0 ? 7 : day; // 1 - 7, Monday is first day of the week
 
-        // 'GMT'
-        case 'Z':
-          if (options.utc) {
-            return "GMT";
-          }
-          else {
-            var tzString = d.toString().match(/\((\w+)\)/);
-            return tzString && tzString[1] || '';
-          }
+                // '1-Jan-1970'
+                case 'v':
+                    return _strftime(_locale.formats.v || '%e-%b-%Y', _d, _locale);
 
-        // '+0000'
-        case 'z':
-          if (options.utc) {
-            return "+0000";
-          }
-          else {
-            var off = typeof tz == 'number' ? tz : -d.getTimezoneOffset();
-            return (off < 0 ? '-' : '+') + pad(Math.abs(off / 60)) + pad(off % 60);
-          }
+                // '00'
+                case 'W':
+                    return pad(weekNumber(_d, 'monday'), padding);
 
-        default: return c;
-      }
-    });
-  }
+                // '4'
+                case 'w':
+                    return _d.getDay(); // 0 - 6, Sunday is first day of the week
 
-  function dateToUTC(d) {
-    var msDelta = (d.getTimezoneOffset() || 0) * 60000;
-    return new Date(d.getTime() + msDelta);
-  }
+                // '1970'
+                case 'Y':
+                    return _d.getFullYear();
 
-  var RequiredDateMethods = ['getTime', 'getTimezoneOffset', 'getDay', 'getDate', 'getMonth', 'getFullYear', 'getYear', 'getHours', 'getMinutes', 'getSeconds'];
-  function quacksLikeDate(x) {
-    var i = 0
-      , n = RequiredDateMethods.length
-      ;
-    for (i = 0; i < n; ++i) {
-      if (typeof x[RequiredDateMethods[i]] != 'function') {
-        return false;
-      }
-    }
-    return true;
-  }
+                // '70'
+                case 'y':
+                    return String(_d.getFullYear()).slice(-2);
 
-  // Default padding is '0' and default length is 2, both are optional.
-  function pad(n, padding, length) {
-    // pad(n, <length>)
-    if (typeof padding === 'number') {
-      length = padding;
-      padding = '0';
+                // 'GMT'
+                case 'Z':
+                    if (_options.utc) {
+                        return 'GMT';
+                    } else {
+                        var tzString = _d.toString().match(/\((\w+)\)/);
+                        return tzString && tzString[1] || '';
+                    }
+
+                // '+0000'
+                case 'z':
+                    if (_options.utc) {
+                        return '+0000';
+                    } else {
+                        var off = typeof tz === 'number' ? tz : -_d.getTimezoneOffset();
+                        return (off < 0 ? '-' : '+') + pad(Math.abs(off / 60)) + pad(off % 60);
+                    }
+
+                default:
+                    return _c;
+            }
+        });
     }
 
-    // Defaults handle pad(n) and pad(n, <padding>)
-    if (padding == null) {
-      padding = '0';
-    }
-    length = length || 2;
+    function dateToUTC(d) {
+        var msDelta = (d.getTimezoneOffset() || 0) * 60000;
 
-    var s = String(n);
-    // padding may be an empty string, don't loop forever if it is
-    if (padding) {
-      while (s.length < length) s = padding + s;
+        return new Date(d.getTime() + msDelta);
     }
-    return s;
-  }
 
-  function hours12(d) {
-    var hour = d.getHours();
-    if (hour == 0) hour = 12;
-    else if (hour > 12) hour -= 12;
-    return hour;
-  }
+    function quacksLikeDate(x) {
+        var index = RequiredDateMethods.length;
 
-  // Get the ordinal suffix for a number: st, nd, rd, or th
-  function ordinal(n) {
-    var i = n % 10
-      , ii = n % 100
-      ;
-    if ((ii >= 11 && ii <= 13) || i === 0 || i >= 4) {
-      return 'th';
+        while (index--) {
+            if (typeof x[RequiredDateMethods[index]] !== 'function') {
+                return false;
+            }
+        }
+
+        return true;
     }
-    switch (i) {
-      case 1: return 'st';
-      case 2: return 'nd';
-      case 3: return 'rd';
-    }
-  }
 
-  // firstWeekday: 'sunday' or 'monday', default is 'sunday'
-  //
-  // Pilfered & ported from Ruby's strftime implementation.
-  function weekNumber(d, firstWeekday) {
-    firstWeekday = firstWeekday || 'sunday';
+    // Default padding is '0' and default length is 2, both are optional.
+    function pad(n, padding) {
+        var _padding = padding == null ? '0' : padding;
+        var _n = String(n);
 
-    // This works by shifting the weekday back by one day if we
-    // are treating Monday as the first day of the week.
-    var wday = d.getDay();
-    if (firstWeekday == 'monday') {
-      if (wday == 0) // Sunday
-        wday = 6;
-      else
-        wday--;
+        // padding may be an empty string, don't loop forever if it is
+        switch (_n.length) {
+            case 0:
+                _n = _padding + _padding;
+                break;
+            case 1:
+                _n = _padding + _n;
+                break;
+        }
+
+        return _n;
     }
-    var firstDayOfYear = new Date(d.getFullYear(), 0, 1)
-      , yday = (d - firstDayOfYear) / 86400000
-      , weekNum = (yday + 7 - wday) / 7
-      ;
-    return Math.floor(weekNum);
-  }
+
+    function hours12(d) {
+        var hour = d.getHours();
+
+        if (hour === 0) {
+            hour = 12;
+        } else if (hour > 12) {
+            hour -= 12;
+        }
+
+        return hour;
+    }
+
+    // Get the ordinal suffix for a number: st, nd, rd, or th
+    function ordinal(n) {
+        var i = n % 10;
+        var ii = n % 100;
+
+        if ((ii >= 11 && ii <= 13) || i === 0 || i >= 4) {
+            return 'th';
+        }
+
+        switch (i) {
+            case 1:
+                return 'st';
+            case 2:
+                return 'nd';
+            case 3:
+                return 'rd';
+        }
+    }
+
+    // firstWeekday: 'sunday' or 'monday', default is 'sunday'
+    // Pilfered & ported from Ruby's strftime implementation.
+    function weekNumber(d, firstWeekday) {
+        var firstDayOfYear = new Date(d.getFullYear(), 0, 1);
+        // This works by shifting the weekday back by one day if we
+        // are treating Monday as the first day of the week.
+        var wDay = d.getDay();
+        var yDay = (d - firstDayOfYear) / 86400000;
+
+        if (firstWeekday === 'monday') {
+            if (wDay === 0){
+                // Sunday
+                wDay = 6;
+            } else {
+                wDay--;
+            }
+        }
+
+        return Math.floor((yDay + 7 - wDay) / 7);
+    }
+
+    namespace.strftime = strftime;
+    namespace.strftimeTZ = strftime.strftimeTZ = strfTimeTZ;
+    namespace.strftimeUTC = strftime.strftimeUTC = strftimeUTC;
+    namespace.localizedStrftime = strftime.localizedStrftime = localizedStrftime;
 
 }());