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@stdlib/utils

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Standard utilities.

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/* * @license Apache-2.0 * * Copyright (c) 2019 The Stdlib Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ // TypeScript Version: 4.1 /// <reference types="@stdlib/types"/> import { Collection } from '@stdlib/types/array'; /** * Interface defining function options. */ interface Options { /** * If `'values'`, values are returned; if `'indices'`, indices are returned; if `'*'`, both indices and values are returned. */ returns?: 'values' | 'indices' | '*'; } /** * Splits values into two groups. * * ## Notes * * - If an element in `filter` is truthy, then the corresponding element in the input collection belongs to the first group; otherwise, the collection element belongs to the second group. * - If provided an empty collection, the function returns an empty array. * * @param collection - input collection * @param filter - collection indicating which group an element in the input collection belongs to * @throws first and last arguments must be the same length * @returns results * * @example * var arr = [ 'beep', 'boop', 'foo', 'bar' ]; * var filter = [ true, true, false, true ]; * * var out = bifurcate( arr, filter ); * // returns [ [ 'beep', 'boop', 'bar' ], [ 'foo' ] ] */ declare function bifurcate<T = unknown>( collection: Collection<T>, filter: Collection ): Array<Array<T>>; /** * Splits values into two groups. * * ## Notes * * - If an element in `filter` is truthy, then the corresponding element in the input collection belongs to the first group; otherwise, the collection element belongs to the second group. * - If provided an empty collection, the function returns an empty array. * * @param collection - input collection * @param options - function options * @param options.returns - if `values`, values are returned; if `indices`, indices are returned; if `*`, both indices and values are returned (default: 'values') * @param filter - collection indicating which group an element in the input collection belongs to * @throws first and last arguments must be the same length * @returns results * * @example * var arr = [ 'beep', 'boop', 'foo', 'bar' ]; * var filter = [ true, true, false, true ]; * * var opts = { * 'returns': 'indices' * }; * * var out = bifurcate( arr, opts, filter ); * // returns [ [ 0, 1, 3 ], [ 2 ] ] * * @example * var arr = [ 'beep', 'boop', 'foo', 'bar' ]; * var filter = [ true, true, false, true ]; * * var opts = { * 'returns': '*' * }; * * var out = bifurcate( arr, opts, filter ); * // returns [ [ [ 0, 'beep' ], [ 1, 'boop' ], [ 3, 'bar' ] ], [ [ 2, 'foo' ] ] ] */ declare function bifurcate<T = unknown>( collection: Collection<T>, options: Options, filter: Collection ): Array<Array<T>>; // EXPORTS // export = bifurcate;