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1 3a515b92 cagy
'use strict';
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var GetIntrinsic = require('../GetIntrinsic');
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var $Number = GetIntrinsic('%Number%');
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var $TypeError = GetIntrinsic('%TypeError%');
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var $isNaN = require('../helpers/isNaN');
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var $isFinite = require('../helpers/isFinite');
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var isPrefixOf = require('../helpers/isPrefixOf');
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var ToNumber = require('./ToNumber');
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var ToPrimitive = require('./ToPrimitive');
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var Type = require('./Type');
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// https://www.ecma-international.org/ecma-262/5.1/#sec-11.8.5
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// eslint-disable-next-line max-statements
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module.exports = function AbstractRelationalComparison(x, y, LeftFirst) {
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	if (Type(LeftFirst) !== 'Boolean') {
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		throw new $TypeError('Assertion failed: LeftFirst argument must be a Boolean');
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	}
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	var px;
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	var py;
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	if (LeftFirst) {
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		px = ToPrimitive(x, $Number);
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		py = ToPrimitive(y, $Number);
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	} else {
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		py = ToPrimitive(y, $Number);
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		px = ToPrimitive(x, $Number);
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	}
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	var bothStrings = Type(px) === 'String' && Type(py) === 'String';
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	if (!bothStrings) {
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		var nx = ToNumber(px);
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		var ny = ToNumber(py);
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		if ($isNaN(nx) || $isNaN(ny)) {
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			return undefined;
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		}
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		if ($isFinite(nx) && $isFinite(ny) && nx === ny) {
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			return false;
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		}
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		if (nx === 0 && ny === 0) {
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			return false;
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		}
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		if (nx === Infinity) {
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			return false;
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		}
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		if (ny === Infinity) {
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			return true;
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		}
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		if (ny === -Infinity) {
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			return false;
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		}
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		if (nx === -Infinity) {
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			return true;
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		}
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		return nx < ny; // by now, these are both nonzero, finite, and not equal
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	}
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	if (isPrefixOf(py, px)) {
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		return false;
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	}
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	if (isPrefixOf(px, py)) {
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		return true;
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	}
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	return px < py; // both strings, neither a prefix of the other. shortcut for steps c-f
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};