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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
/**
* Compare two arrays or strings by performing strict equality check for each value.
* @template T [T=any]
* @param {ArrayLike<T>} a Array of values to be compared
* @param {ArrayLike<T>} b Array of values to be compared
* @returns {boolean} returns true if all the elements of passed arrays are strictly equal.
*/
module.exports.equals = (a, b) => {
if (a.length !== b.length) return false;
for (let i = 0; i < a.length; i++) {
if (a[i] !== b[i]) return false;
}
return true;
};
/**
* Partition an array by calling a predicate function on each value.
* @template T [T=any]
* @param {Array<T>} arr Array of values to be partitioned
* @param {(value: T) => boolean} fn Partition function which partitions based on truthiness of result.
* @returns {[Array<T>, Array<T>]} returns the values of `arr` partitioned into two new arrays based on fn predicate.
*/
module.exports.groupBy = (
// eslint-disable-next-line default-param-last
arr = [],
fn
) =>
arr.reduce(
/**
* @param {[Array<T>, Array<T>]} groups An accumulator storing already partitioned values returned from previous call.
* @param {T} value The value of the current element
* @returns {[Array<T>, Array<T>]} returns an array of partitioned groups accumulator resulting from calling a predicate on the current value.
*/
(groups, value) => {
groups[fn(value) ? 0 : 1].push(value);
return groups;
},
[[], []]
);
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