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- import reduceBy from "./reduceBy.js";
- /**
- * Counts the elements of a list according to how many match each value of a
- * key generated by the supplied function. Returns an object mapping the keys
- * produced by `fn` to the number of occurrences in the list. Note that all
- * keys are coerced to strings because of how JavaScript objects work.
- *
- * Acts as a transducer if a transformer is given in list position.
- *
- * @func
- * @memberOf R
- * @since v0.1.0
- * @category Relation
- * @sig (a -> String) -> [a] -> {*}
- * @param {Function} fn The function used to map values to keys.
- * @param {Array} list The list to count elements from.
- * @return {Object} An object mapping keys to number of occurrences in the list.
- * @example
- *
- * const numbers = [1.0, 1.1, 1.2, 2.0, 3.0, 2.2];
- * R.countBy(Math.floor)(numbers); //=> {'1': 3, '2': 2, '3': 1}
- *
- * const letters = ['a', 'b', 'A', 'a', 'B', 'c'];
- * R.countBy(R.toLower)(letters); //=> {'a': 3, 'b': 2, 'c': 1}
- */
- var countBy =
- /*#__PURE__*/
- reduceBy(function (acc, elem) {
- return acc + 1;
- }, 0);
- export default countBy;
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