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// String.fromCodePoint
/*! http://mths.be/fromcodepoint v0.1.0 by @mathias */
(function() {
	var stringFromCharCode = String.fromCharCode;
	var floor = Math.floor;
	var fromCodePoint = function() {
		var MAX_SIZE = 0x4000;
		var codeUnits = [];
		var highSurrogate;
		var lowSurrogate;
		var index = -1;
		var length = arguments.length;
		if (!length) {
			return '';
		}
		var result = '';
		while (++index < length) {
			var codePoint = Number(arguments[index]);
			if (
				!isFinite(codePoint) ||       // `NaN`, `+Infinity`, or `-Infinity`
				codePoint < 0 ||              // not a valid Unicode code point
				codePoint > 0x10FFFF ||       // not a valid Unicode code point
				floor(codePoint) != codePoint // not an integer
			) {
				throw RangeError('Invalid code point: ' + codePoint);
			}
			if (codePoint <= 0xFFFF) { // BMP code point
				codeUnits.push(codePoint);
			} else { // Astral code point; split in surrogate halves
				// http://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
				codePoint -= 0x10000;
				highSurrogate = (codePoint >> 10) + 0xD800;
				lowSurrogate = (codePoint % 0x400) + 0xDC00;
				codeUnits.push(highSurrogate, lowSurrogate);
			}
			if (index + 1 == length || codeUnits.length > MAX_SIZE) {
				result += stringFromCharCode.apply(null, codeUnits);
				codeUnits.length = 0;
			}
		}
		return result;
	};
	if (Object.defineProperty) {
		Object.defineProperty(String, 'fromCodePoint', {
			'value': fromCodePoint,
			'configurable': true,
			'writable': true
		});
	} else {
		String.fromCodePoint = fromCodePoint;
	}
}());