xdate.dev.js 18.5 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802
/**
 * @preserve XDate v0.7
 * Docs & Licensing: http://arshaw.com/xdate/
 */

/*
 * Internal Architecture
 * ---------------------
 * An XDate wraps a native Date. The native Date is stored in the '0' property of the object.
 * UTC-mode is determined by whether the internal native Date's toString method is set to
 * Date.prototype.toUTCString (see getUTCMode).
 *
 */

var XDate = (function(Date, Math, Array, undefined) {


/** @const */ var FULLYEAR     = 0;
/** @const */ var MONTH        = 1;
/** @const */ var DATE         = 2;
/** @const */ var HOURS        = 3;
/** @const */ var MINUTES      = 4;
/** @const */ var SECONDS      = 5;
/** @const */ var MILLISECONDS = 6;
/** @const */ var DAY          = 7;
/** @const */ var YEAR         = 8;
/** @const */ var WEEK         = 9;
/** @const */ var DAY_MS = 86400000;
var ISO_FORMAT_STRING = "yyyy-MM-dd'T'HH:mm:ss(.fff)";
var ISO_FORMAT_STRING_TZ = ISO_FORMAT_STRING + "zzz";


var methodSubjects = [
	'FullYear',     // 0
	'Month',        // 1
	'Date',         // 2
	'Hours',        // 3
	'Minutes',      // 4
	'Seconds',      // 5
	'Milliseconds', // 6
	'Day',          // 7
	'Year'          // 8
];
var subjectPlurals = [
	'Years',        // 0
	'Months',       // 1
	'Days'          // 2
];
var unitsWithin = [
	12,   // months in year
	31,   // days in month (sort of)
	24,   // hours in day
	60,   // minutes in hour
	60,   // seconds in minute
	1000, // milliseconds in second
	1     //
];
var formatStringRE = new RegExp(
	"(([a-zA-Z])\\2*)|" + // 1, 2
	"(\\(" + "(('.*?'|\\(.*?\\)|.)*?)" + "\\))|" + // 3, 4, 5 (allows for 1 level of inner quotes or parens)
	"('(.*?)')" // 6, 7
);
var UTC = Date.UTC;
var toUTCString = Date.prototype.toUTCString;
var proto = XDate.prototype;



// This makes an XDate look pretty in Firebug and Web Inspector.
// It makes an XDate seem array-like, and displays [ <internal-date>.toString() ]
proto.length = 1;
proto.splice = Array.prototype.splice;




/* Constructor
---------------------------------------------------------------------------------*/


function XDate() {
	return init(
		(this instanceof XDate) ? this : new XDate(),
		arguments
	);
}


function init(xdate, args) {
	var len = args.length;
	var utcMode;
	if (isBoolean(args[len-1])) {
		utcMode = args[--len];
		args = slice(args, 0, len);
	}
	if (!len) {
		xdate[0] = new Date();
	}
	else if (len == 1) {
		var arg = args[0];
		if (arg instanceof Date || isNumber(arg)) {
			xdate[0] = new Date(+arg);
		}
		else if (arg instanceof XDate) {
			xdate[0] = _clone(arg);
		}
		else if (isString(arg)) {
			xdate[0] = new Date(0);
			xdate = parse(arg, utcMode || false, xdate);
		}
	}
	else {
		xdate[0] = new Date(UTC.apply(Date, args));
		if (!utcMode) {
			xdate[0] = coerceToLocal(xdate[0]);
		}
	}
	if (isBoolean(utcMode)) {
		setUTCMode(xdate, utcMode);
	}
	return xdate;
}



/* UTC Mode Methods
---------------------------------------------------------------------------------*/


proto.getUTCMode = methodize(getUTCMode);
function getUTCMode(xdate) {
	return xdate[0].toString === toUTCString;
};


proto.setUTCMode = methodize(setUTCMode);
function setUTCMode(xdate, utcMode, doCoercion) {
	if (utcMode) {
		if (!getUTCMode(xdate)) {
			if (doCoercion) {
				xdate[0] = coerceToUTC(xdate[0]);
			}
			xdate[0].toString = toUTCString;
		}
	}else{
		if (getUTCMode(xdate)) {
			if (doCoercion) {
				xdate[0] = coerceToLocal(xdate[0]);
			}else{
				xdate[0] = new Date(+xdate[0]);
			}
			// toString will have been cleared
		}
	}
	return xdate; // for chaining
}


proto.getTimezoneOffset = function() {
	if (getUTCMode(this)) {
		return 0;
	}else{
		return this[0].getTimezoneOffset();
	}
};



/* get / set / add / diff Methods (except for week-related)
---------------------------------------------------------------------------------*/


each(methodSubjects, function(subject, fieldIndex) {

	proto['get' + subject] = function() {
		return _getField(this[0], getUTCMode(this), fieldIndex);
	};
	
	if (fieldIndex != YEAR) { // because there is no getUTCYear
	
		proto['getUTC' + subject] = function() {
			return _getField(this[0], true, fieldIndex);
		};
		
	}

	if (fieldIndex != DAY) { // because there is no setDay or setUTCDay
	                         // and the add* and diff* methods use DATE instead
		
		proto['set' + subject] = function(value) {
			_set(this, fieldIndex, value, arguments, getUTCMode(this));
			return this; // for chaining
		};
		
		if (fieldIndex != YEAR) { // because there is no setUTCYear
		                          // and the add* and diff* methods use FULLYEAR instead
			
			proto['setUTC' + subject] = function(value) {
				_set(this, fieldIndex, value, arguments, true);
				return this; // for chaining
			};
			
			proto['add' + (subjectPlurals[fieldIndex] || subject)] = function(delta, preventOverflow) {
				_add(this, fieldIndex, delta, preventOverflow);
				return this; // for chaining
			};
			
			proto['diff' + (subjectPlurals[fieldIndex] || subject)] = function(otherDate) {
				return _diff(this, otherDate, fieldIndex);
			};
			
		}
		
	}

});


function _set(xdate, fieldIndex, value, args, useUTC) {
	var getField = curry(_getField, xdate[0], useUTC);
	var setField = curry(_setField, xdate[0], useUTC);
	var month = fieldIndex == MONTH ? value % 12 : getField(MONTH);
	var preventOverflow = false;
	if (args.length == 2 && isBoolean(args[1])) {
		preventOverflow = args[1];
		args = [value];
	}
	setField(fieldIndex, args);
	if (preventOverflow && getField(MONTH) != month) {
		setField(MONTH, [ getField(MONTH) - 1 ]);
		setField(DATE, [ getDaysInMonth(getField(FULLYEAR), getField(MONTH)) ]);
	}
}


function _add(xdate, fieldIndex, delta, preventOverflow) {
	delta = Number(delta);
	var intDelta = Math.floor(delta);
	xdate['set' + methodSubjects[fieldIndex]](
		xdate['get' + methodSubjects[fieldIndex]]() + intDelta,
		preventOverflow || false
	);
	if (intDelta != delta && fieldIndex < MILLISECONDS) {
		_add(xdate, fieldIndex+1, (delta-intDelta)*unitsWithin[fieldIndex], preventOverflow);
	}
}


function _diff(xdate1, xdate2, fieldIndex) { // fieldIndex=FULLYEAR is for years, fieldIndex=DATE is for days
	xdate1 = xdate1.clone().setUTCMode(true, true);
	xdate2 = XDate(xdate2).setUTCMode(true, true);
	var v = 0;
	if (fieldIndex == FULLYEAR || fieldIndex == MONTH) {
		for (var i=MILLISECONDS, methodName; i>=fieldIndex; i--) {
			v /= unitsWithin[i];
			v += _getField(xdate2, false, i) - _getField(xdate1, false, i);
		}
		if (fieldIndex == MONTH) {
			v += (xdate2.getFullYear() - xdate1.getFullYear()) * 12;
		}
	}
	else if (fieldIndex == DATE) {
		var clear1 = xdate1.toDate().setUTCHours(0, 0, 0, 0); // returns an ms value
		var clear2 = xdate2.toDate().setUTCHours(0, 0, 0, 0); // returns an ms value
		v = Math.round((clear2 - clear1) / DAY_MS) + ((xdate2 - clear2) - (xdate1 - clear1)) / DAY_MS;
	}
	else {
		v = (xdate2 - xdate1) / [
			3600000, // milliseconds in hour
			60000,   // milliseconds in minute
			1000,    // milliseconds in second
			1        //
			][fieldIndex - 3];
	}
	return v;
}



/* Week Methods
---------------------------------------------------------------------------------*/


proto.getWeek = function() {
	return _getWeek(curry(_getField, this, false));
};


proto.getUTCWeek = function() {
	return _getWeek(curry(_getField, this, true));
};


proto.setWeek = function(n, year) {
	_setWeek(this, n, year, false);
	return this; // for chaining
};


proto.setUTCWeek = function(n, year) {
	_setWeek(this, n, year, true);
	return this; // for chaining
};


proto.addWeeks = function(delta) {
	return this.addDays(Number(delta) * 7);
};


proto.diffWeeks = function(otherDate) {
	return _diff(this, otherDate, DATE) / 7;
};


function _getWeek(getField) {
	return getWeek(getField(FULLYEAR), getField(MONTH), getField(DATE));
}


function getWeek(year, month, date) {
	var d = new Date(UTC(year, month, date));
	var currentWeek1 = getWeek1(year);
	var week1 = currentWeek1;
	if (d < currentWeek1) {
		week1 = getWeek1(year-1);
	}else{
		var nextWeek1 = getWeek1(year+1);
		if (d >= nextWeek1) {
			week1 = nextWeek1;
		}
	}
	return Math.floor(Math.round((d - week1) / DAY_MS) / 7) + 1;
}


function getWeek1(year) { // returns Date of first week of year, in UTC
	var d = new Date(UTC(year, 0, 4));
	d.setUTCDate(d.getUTCDate() - (d.getUTCDay() + 6) % 7); // make it Monday of the week
	return d;
}


function _setWeek(xdate, n, year, useUTC) {
	var getField = curry(_getField, xdate, useUTC);
	var setField = curry(_setField, xdate, useUTC);
	var d = getWeek1(year===undefined ? getField(FULLYEAR) : year);
	if (!useUTC) {
		d = coerceToLocal(d);
	}
	xdate.setTime(+d);
	setField(DATE, [ getField(DATE) + (n-1) * 7 ]); // would have used xdate.addUTCWeeks :(
		// n-1 because n is 1-based
}



/* Parsing
---------------------------------------------------------------------------------*/


XDate.parsers = [
	parseISO
];


XDate.parse = function(str) {
	return +XDate(''+str);
};


function parse(str, utcMode, xdate) {
	var parsers = XDate.parsers;
	var i = 0;
	var res;
	for (; i<parsers.length; i++) {
		res = parsers[i](str, utcMode, xdate);
		if (res) {
			return res;
		}
	}
	xdate[0] = new Date(str);
	return xdate;
}


function parseISO(str, utcMode, xdate) {
	var m = str.match(/^(\d{4})(-(\d{2})(-(\d{2})([T ](\d{2}):(\d{2})(:(\d{2})(\.(\d+))?)?(Z|(([-+])(\d{2})(:?(\d{2}))?))?)?)?)?$/);
	if (m) {
		var d = new Date(UTC(
			m[1],
			m[3] ? m[3] - 1 : 0,
			m[5] || 1,
			m[7] || 0,
			m[8] || 0,
			m[10] || 0,
			m[12] ? Number('0.' + m[12]) * 1000 : 0
		));
		if (m[13]) { // has gmt offset or Z
			if (m[14]) { // has gmt offset
				d.setUTCMinutes(
					d.getUTCMinutes() +
					(m[15] == '-' ? 1 : -1) * (Number(m[16]) * 60 + (m[18] ? Number(m[18]) : 0))
				);
			}
		}else{ // no specified timezone
			if (!utcMode) {
				d = coerceToLocal(d);
			}
		}
		return xdate.setTime(+d);
	}
}



/* Formatting
---------------------------------------------------------------------------------*/


proto.toString = function(formatString, settings, uniqueness) {
	if (formatString === undefined || !valid(this)) {
		return this[0].toString(); // already accounts for utc-mode (might be toUTCString)
	}else{
		return format(this, formatString, settings, uniqueness, getUTCMode(this));
	}
};


proto.toUTCString = proto.toGMTString = function(formatString, settings, uniqueness) {
	if (formatString === undefined || !valid(this)) {
		return this[0].toUTCString();
	}else{
		return format(this, formatString, settings, uniqueness, true);
	}
};


proto.toISOString = function() {
	return this.toUTCString(ISO_FORMAT_STRING_TZ);
};


XDate.defaultLocale = '';
XDate.locales = {
	'': {
		monthNames: ['January','February','March','April','May','June','July','August','September','October','November','December'],
		monthNamesShort: ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'],
		dayNames: ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'],
		dayNamesShort: ['Sun','Mon','Tue','Wed','Thu','Fri','Sat'],
		amDesignator: 'AM',
		pmDesignator: 'PM'
	}
};
XDate.formatters = {
	i: ISO_FORMAT_STRING,
	u: ISO_FORMAT_STRING_TZ
};


function format(xdate, formatString, settings, uniqueness, useUTC) {

	var locales = XDate.locales;
	var defaultLocaleSettings = locales[XDate.defaultLocale] || {};
	var getField = curry(_getField, xdate, useUTC);
	
	settings = (isString(settings) ? locales[settings] : settings) || {};
	
	function getSetting(name) {
		return settings[name] || defaultLocaleSettings[name];
	}
	
	function getFieldAndTrace(fieldIndex) {
		if (uniqueness) {
			var i = (fieldIndex == DAY ? DATE : fieldIndex) - 1;
			for (; i>=0; i--) {
				uniqueness.push(getField(i));
			}
		}
		return getField(fieldIndex);
	}
	
	return _format(xdate, formatString, getFieldAndTrace, getSetting, useUTC);
}


function _format(xdate, formatString, getField, getSetting, useUTC) {
	var m;
	var subout;
	var out = '';
	while (m = formatString.match(formatStringRE)) {
		out += formatString.substr(0, m.index);
		if (m[1]) { // consecutive alphabetic characters
			out += processTokenString(xdate, m[1], getField, getSetting, useUTC);
		}
		else if (m[3]) { // parenthesis
			subout = _format(xdate, m[4], getField, getSetting, useUTC);
			if (parseInt(subout.replace(/\D/g, ''), 10)) { // if any of the numbers are non-zero. or no numbers at all
				out += subout;
			}
		}
		else { // else if (m[6]) { // single quotes
			out += m[7] || "'"; // if inner is blank, meaning 2 consecutive quotes = literal single quote
		}
		formatString = formatString.substr(m.index + m[0].length);
	}
	return out + formatString;
}


function processTokenString(xdate, tokenString, getField, getSetting, useUTC) {
	var end = tokenString.length;
	var replacement;
	var out = '';
	while (end > 0) {
		replacement = getTokenReplacement(xdate, tokenString.substr(0, end), getField, getSetting, useUTC);
		if (replacement !== undefined) {
			out += replacement;
			tokenString = tokenString.substr(end);
			end = tokenString.length;
		}else{
			end--;
		}
	}
	return out + tokenString;
}


function getTokenReplacement(xdate, token, getField, getSetting, useUTC) {
	var formatter = XDate.formatters[token];
	if (isString(formatter)) {
		return _format(xdate, formatter, getField, getSetting, useUTC);
	}
	else if (isFunction(formatter)) {
		return formatter(xdate, useUTC || false, getSetting);
	}
	switch (token) {
		case 'fff'  : return zeroPad(getField(MILLISECONDS), 3);
		case 's'    : return getField(SECONDS);
		case 'ss'   : return zeroPad(getField(SECONDS));
		case 'm'    : return getField(MINUTES);
		case 'mm'   : return zeroPad(getField(MINUTES));
		case 'h'    : return getField(HOURS) % 12 || 12;
		case 'hh'   : return zeroPad(getField(HOURS) % 12 || 12);
		case 'H'    : return getField(HOURS);
		case 'HH'   : return zeroPad(getField(HOURS));
		case 'd'    : return getField(DATE);
		case 'dd'   : return zeroPad(getField(DATE));
		case 'ddd'  : return getSetting('dayNamesShort')[getField(DAY)] || '';
		case 'dddd' : return getSetting('dayNames')[getField(DAY)] || '';
		case 'M'    : return getField(MONTH) + 1;
		case 'MM'   : return zeroPad(getField(MONTH) + 1);
		case 'MMM'  : return getSetting('monthNamesShort')[getField(MONTH)] || '';
		case 'MMMM' : return getSetting('monthNames')[getField(MONTH)] || '';
		case 'yy'   : return (getField(FULLYEAR)+'').substring(2);
		case 'yyyy' : return getField(FULLYEAR);
		case 't'    : return _getDesignator(getField, getSetting).substr(0, 1).toLowerCase();
		case 'tt'   : return _getDesignator(getField, getSetting).toLowerCase();
		case 'T'    : return _getDesignator(getField, getSetting).substr(0, 1);
		case 'TT'   : return _getDesignator(getField, getSetting);
		case 'z'    :
		case 'zz'   :
		case 'zzz'  : return useUTC ? 'Z' : _getTZString(xdate, token);
		case 'w'    : return _getWeek(getField);
		case 'ww'   : return zeroPad(_getWeek(getField));
		case 'S'    :
			var d = getField(DATE);
			if (d > 10 && d < 20) return 'th';
			return ['st', 'nd', 'rd'][d % 10 - 1] || 'th';
	}
}


function _getTZString(xdate, token) {
	var tzo = xdate.getTimezoneOffset();
	var sign = tzo < 0 ? '+' : '-';
	var hours = Math.floor(Math.abs(tzo) / 60);
	var minutes = Math.abs(tzo) % 60;
	var out = hours;
	if (token == 'zz') {
		out = zeroPad(hours);
	}
	else if (token == 'zzz') {
		out = zeroPad(hours) + ':' + zeroPad(minutes);
	}
	return sign + out;
}


function _getDesignator(getField, getSetting) {
	return getField(HOURS) < 12 ? getSetting('amDesignator') : getSetting('pmDesignator');
}



/* Misc Methods
---------------------------------------------------------------------------------*/


each(
	[ // other getters
		'getTime',
		'valueOf',
		'toDateString',
		'toTimeString',
		'toLocaleString',
		'toLocaleDateString',
		'toLocaleTimeString',
		'toJSON'
	],
	function(methodName) {
		proto[methodName] = function() {
			return this[0][methodName]();
		};
	}
);


proto.setTime = function(t) {
	this[0].setTime(t);
	return this; // for chaining
};


proto.valid = methodize(valid);
function valid(xdate) {
	return !isNaN(+xdate[0]);
}


proto.clone = function() {
	return new XDate(this);
};


proto.clearTime = function() {
	return this.setHours(0, 0, 0, 0); // will return an XDate for chaining
};


proto.toDate = function() {
	return new Date(+this[0]);
};



/* Misc Class Methods
---------------------------------------------------------------------------------*/


XDate.now = function() {
	return +new Date();
};


XDate.today = function() {
	return new XDate().clearTime();
};


XDate.UTC = UTC;


XDate.getDaysInMonth = getDaysInMonth;



/* Internal Utilities
---------------------------------------------------------------------------------*/


function _clone(xdate) { // returns the internal Date object that should be used
	var d = new Date(+xdate[0]);
	if (getUTCMode(xdate)) {
		d.toString = toUTCString;
	}
	return d;
}


function _getField(d, useUTC, fieldIndex) {
	return d['get' + (useUTC ? 'UTC' : '') + methodSubjects[fieldIndex]]();
}


function _setField(d, useUTC, fieldIndex, args) {
	d['set' + (useUTC ? 'UTC' : '') + methodSubjects[fieldIndex]].apply(d, args);
}



/* Date Math Utilities
---------------------------------------------------------------------------------*/


function coerceToUTC(date) {
	return new Date(UTC(
		date.getFullYear(),
		date.getMonth(),
		date.getDate(),
		date.getHours(),
		date.getMinutes(),
		date.getSeconds(),
		date.getMilliseconds()
	));
}


function coerceToLocal(date) {
	return new Date(
		date.getUTCFullYear(),
		date.getUTCMonth(),
		date.getUTCDate(),
		date.getUTCHours(),
		date.getUTCMinutes(),
		date.getUTCSeconds(),
		date.getUTCMilliseconds()
	);
}


function getDaysInMonth(year, month) {
	return 32 - new Date(UTC(year, month, 32)).getUTCDate();
}



/* General Utilities
---------------------------------------------------------------------------------*/


function methodize(f) {
	return function() {
		return f.apply(undefined, [this].concat(slice(arguments)));
	};
}


function curry(f) {
	var firstArgs = slice(arguments, 1);
	return function() {
		return f.apply(undefined, firstArgs.concat(slice(arguments)));
	};
}


function slice(a, start, end) {
	return Array.prototype.slice.call(
		a,
		start || 0, // start and end cannot be undefined for IE
		end===undefined ? a.length : end
	);
}


function each(a, f) {
	for (var i=0; i<a.length; i++) {
		f(a[i], i);
	};
}


function isString(arg) {
	return typeof arg == 'string';
}


function isNumber(arg) {
	return typeof arg == 'number';
}


function isBoolean(arg) {
	return typeof arg == 'boolean';
}


function isFunction(arg) {
	return typeof arg == 'function';
}


function zeroPad(n, len) {
	len = len || 2;
	n += '';
	while (n.length < len) {
		n = '0' + n;
	}
	return n;
}



// Export for Node.js
if (typeof module !== 'undefined' && module.exports) {
	module.exports = XDate;
}


return XDate;

})(Date, Math, Array);