test-action-debian-package/node_modules/ramda/src/reduceBy.js
Dawid Dziurla 9308795b8b
update
2020-03-26 15:37:35 +01:00

79 lines
2.3 KiB
JavaScript

var _clone =
/*#__PURE__*/
require("./internal/_clone");
var _curryN =
/*#__PURE__*/
require("./internal/_curryN");
var _dispatchable =
/*#__PURE__*/
require("./internal/_dispatchable");
var _has =
/*#__PURE__*/
require("./internal/_has");
var _reduce =
/*#__PURE__*/
require("./internal/_reduce");
var _xreduceBy =
/*#__PURE__*/
require("./internal/_xreduceBy");
/**
* Groups the elements of the list according to the result of calling
* the String-returning function `keyFn` on each element and reduces the elements
* of each group to a single value via the reducer function `valueFn`.
*
* This function is basically a more general [`groupBy`](#groupBy) function.
*
* Acts as a transducer if a transformer is given in list position.
*
* @func
* @memberOf R
* @since v0.20.0
* @category List
* @sig ((a, b) -> a) -> a -> (b -> String) -> [b] -> {String: a}
* @param {Function} valueFn The function that reduces the elements of each group to a single
* value. Receives two values, accumulator for a particular group and the current element.
* @param {*} acc The (initial) accumulator value for each group.
* @param {Function} keyFn The function that maps the list's element into a key.
* @param {Array} list The array to group.
* @return {Object} An object with the output of `keyFn` for keys, mapped to the output of
* `valueFn` for elements which produced that key when passed to `keyFn`.
* @see R.groupBy, R.reduce
* @example
*
* const groupNames = (acc, {name}) => acc.concat(name)
* const toGrade = ({score}) =>
* score < 65 ? 'F' :
* score < 70 ? 'D' :
* score < 80 ? 'C' :
* score < 90 ? 'B' : 'A'
*
* var students = [
* {name: 'Abby', score: 83},
* {name: 'Bart', score: 62},
* {name: 'Curt', score: 88},
* {name: 'Dora', score: 92},
* ]
*
* reduceBy(groupNames, [], toGrade, students)
* //=> {"A": ["Dora"], "B": ["Abby", "Curt"], "F": ["Bart"]}
*/
var reduceBy =
/*#__PURE__*/
_curryN(4, [],
/*#__PURE__*/
_dispatchable([], _xreduceBy, function reduceBy(valueFn, valueAcc, keyFn, list) {
return _reduce(function (acc, elt) {
var key = keyFn(elt);
acc[key] = valueFn(_has(key, acc) ? acc[key] : _clone(valueAcc, [], [], false), elt);
return acc;
}, {}, list);
}));
module.exports = reduceBy;