test-action-debian-package/node_modules/ramda/es/groupBy.js

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2020-03-26 14:37:35 +00:00
import _checkForMethod from "./internal/_checkForMethod.js";
import _curry2 from "./internal/_curry2.js";
import reduceBy from "./reduceBy.js";
/**
* Splits a list into sub-lists stored in an object, based on the result of
* calling a String-returning function on each element, and grouping the
* results according to values returned.
*
* Dispatches to the `groupBy` method of the second argument, if present.
*
* Acts as a transducer if a transformer is given in list position.
*
* @func
* @memberOf R
* @since v0.1.0
* @category List
* @sig (a -> String) -> [a] -> {String: [a]}
* @param {Function} fn Function :: a -> String
* @param {Array} list The array to group
* @return {Object} An object with the output of `fn` for keys, mapped to arrays of elements
* that produced that key when passed to `fn`.
* @see R.reduceBy, R.transduce
* @example
*
* const byGrade = R.groupBy(function(student) {
* const score = student.score;
* return score < 65 ? 'F' :
* score < 70 ? 'D' :
* score < 80 ? 'C' :
* score < 90 ? 'B' : 'A';
* });
* const students = [{name: 'Abby', score: 84},
* {name: 'Eddy', score: 58},
* // ...
* {name: 'Jack', score: 69}];
* byGrade(students);
* // {
* // 'A': [{name: 'Dianne', score: 99}],
* // 'B': [{name: 'Abby', score: 84}]
* // // ...,
* // 'F': [{name: 'Eddy', score: 58}]
* // }
*/
var groupBy =
/*#__PURE__*/
_curry2(
/*#__PURE__*/
_checkForMethod('groupBy',
/*#__PURE__*/
reduceBy(function (acc, item) {
if (acc == null) {
acc = [];
}
acc.push(item);
return acc;
}, null)));
export default groupBy;