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// derived from https://github.com/mathiasbynens/String.fromCodePoint
/*! http://mths.be/fromcodepoint v0.2.1 by @mathias */
if (String.fromCodePoint) {
module.exports = function (_) {
try {
return String.fromCodePoint(_);
} catch (e) {
if (e instanceof RangeError) {
return String.fromCharCode(0xFFFD);
}
throw e;
}
}
} else {
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
) {
return String.fromCharCode(0xFFFD);
}
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;
};
module.exports = fromCodePoint;
}
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