28 lines
709 B
JavaScript
28 lines
709 B
JavaScript
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import _reduce from "./internal/_reduce.js";
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import curry from "./curry.js";
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/**
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* Returns the number of items in a given `list` matching the predicate `f`
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*
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* @func
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* @memberOf R
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* @since v0.28.0
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* @category List
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* @sig (a -> Boolean) -> [a] -> Number
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* @param {Function} predicate to match items against
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* @return {Array} list of items to count in
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* @example
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*
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* const even = x => x % 2 == 0;
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*
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* R.count(even, [1, 2, 3, 4, 5]); // => 2
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* R.map(R.count(even), [[1, 1, 1], [2, 3, 4, 5], [6]]); // => [0, 2, 1]
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*/
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var count =
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/*#__PURE__*/
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curry(function (pred, list) {
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return _reduce(function (a, e) {
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return pred(e) ? a + 1 : a;
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}, 0, list);
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});
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export default count;
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