47 lines
1.3 KiB
JavaScript
47 lines
1.3 KiB
JavaScript
'use strict';
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var aSet = require('../internals/a-set');
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var SetHelpers = require('../internals/set-helpers');
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var size = require('../internals/set-size');
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var getSetRecord = require('../internals/get-set-record');
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var iterateSet = require('../internals/set-iterate');
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var iterateSimple = require('../internals/iterate-simple');
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var Set = SetHelpers.Set;
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var add = SetHelpers.add;
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var has = SetHelpers.has;
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var nativeHas = SetHelpers.$has;
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var nativeKeys = SetHelpers.$keys;
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var isNativeSetRecord = function (record) {
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return record.has === nativeHas && record.keys === nativeKeys;
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};
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// `Set.prototype.intersection` method
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// https://github.com/tc39/proposal-set-methods
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module.exports = function intersection(other) {
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var O = aSet(this);
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var otherRec = getSetRecord(other);
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var result = new Set();
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// observable side effects
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if (!isNativeSetRecord(otherRec) && size(O) > otherRec.size) {
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iterateSimple(otherRec.getIterator(), function (e) {
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if (has(O, e)) add(result, e);
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});
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if (size(result) < 2) return result;
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var disordered = result;
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result = new Set();
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iterateSet(O, function (e) {
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if (has(disordered, e)) add(result, e);
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});
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} else {
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iterateSet(O, function (e) {
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if (otherRec.includes(e)) add(result, e);
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});
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}
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return result;
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};
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