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- /**
- * Copyright (c) 2013-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- *
- */
-
- 'use strict';
-
- var Set = require('./Set');
-
- var emptyFunction = require('./emptyFunction');
-
- /**
- * Returns the count of distinct elements selected from an array.
- */
- function countDistinct(iter, selector) {
- selector = selector || emptyFunction.thatReturnsArgument;
-
- var set = new Set();
- var _iteratorNormalCompletion = true;
- var _didIteratorError = false;
- var _iteratorError = undefined;
-
- try {
- for (var _iterator = iter[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
- var val = _step.value;
-
- set.add(selector(val));
- }
- } catch (err) {
- _didIteratorError = true;
- _iteratorError = err;
- } finally {
- try {
- if (!_iteratorNormalCompletion && _iterator['return']) {
- _iterator['return']();
- }
- } finally {
- if (_didIteratorError) {
- throw _iteratorError;
- }
- }
- }
-
- return set.size;
- }
-
- module.exports = countDistinct;
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