44 lines
1.1 KiB
JavaScript
44 lines
1.1 KiB
JavaScript
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import _Set from "./internal/_Set.js";
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import _curry2 from "./internal/_curry2.js";
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/**
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* Returns a new list containing only one copy of each element in the original
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* list, based upon the value returned by applying the supplied function to
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* each list element. Prefers the first item if the supplied function produces
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* the same value on two items. [`R.equals`](#equals) is used for comparison.
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*
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* @func
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* @memberOf R
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* @since v0.16.0
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* @category List
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* @sig (a -> b) -> [a] -> [a]
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* @param {Function} fn A function used to produce a value to use during comparisons.
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* @param {Array} list The array to consider.
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* @return {Array} The list of unique items.
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* @example
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*
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* R.uniqBy(Math.abs, [-1, -5, 2, 10, 1, 2]); //=> [-1, -5, 2, 10]
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*/
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var uniqBy =
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/*#__PURE__*/
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_curry2(function uniqBy(fn, list) {
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var set = new _Set();
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var result = [];
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var idx = 0;
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var appliedItem, item;
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while (idx < list.length) {
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item = list[idx];
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appliedItem = fn(item);
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if (set.add(appliedItem)) {
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result.push(item);
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}
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idx += 1;
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}
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return result;
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});
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export default uniqBy;
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