35 lines
1.1 KiB
JavaScript
35 lines
1.1 KiB
JavaScript
var bind = require('../internals/function-bind-context');
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var IndexedObject = require('../internals/indexed-object');
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var toObject = require('../internals/to-object');
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var toLength = require('../internals/to-length');
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// `Array.prototype.{ findLast, findLastIndex }` methods implementation
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var createMethod = function (TYPE) {
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var IS_FIND_INDEX = TYPE == 6;
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return function ($this, callbackfn, that) {
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var O = toObject($this);
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var self = IndexedObject(O);
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var boundFunction = bind(callbackfn, that, 3);
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var index = toLength(self.length);
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var value, result;
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while (index-- > 0) {
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value = self[index];
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result = boundFunction(value, index, O);
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if (result) switch (TYPE) {
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case 5: return value; // find
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case 6: return index; // findIndex
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}
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}
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return IS_FIND_INDEX ? -1 : undefined;
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};
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};
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module.exports = {
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// `Array.prototype.findLast` method
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// https://github.com/tc39/proposal-array-find-from-last
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findLast: createMethod(5),
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// `Array.prototype.findLastIndex` method
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// https://github.com/tc39/proposal-array-find-from-last
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findLastIndex: createMethod(6)
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};
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