action-debian-package/node_modules/ramda/es/countBy.js

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2020-03-26 14:37:35 +00:00
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;