fast-cartesian
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Fast cartesian product
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TypeScript
import { type Inputs } from './validate.js';
/**
* Returns a two-dimensional `Array` where each row is a combination of
* `inputs`.
*
* @example
* ```js
* console.log(
* fastCartesian([
* ['red', 'blue'],
* ['circle', 'square'],
* ]),
* )
* // [
* // [ 'red', 'circle' ],
* // [ 'red', 'square' ],
* // [ 'blue', 'circle' ],
* // [ 'blue', 'square' ]
* // ]
*
* // Return initial indexes
* console.log(
* fastCartesian(
* [
* ['red', 'blue'],
* ['circle', 'square'],
* ].map(Object.entries),
* ),
* )
* // [
* // [ [ '0', 'red' ], [ '0', 'circle' ] ],
* // [ [ '0', 'red' ], [ '1', 'square' ] ],
* // [ [ '1', 'blue' ], [ '0', 'circle' ] ],
* // [ [ '1', 'blue' ], [ '1', 'square' ] ]
* // ]
* ```
*/
declare const fastCartesian: <InputArrays extends Inputs>(inputs: readonly [...InputArrays]) => CartesianProduct<InputArrays>;
export default fastCartesian;
type CartesianProduct<InputArrays extends Inputs> = InputArrays extends readonly [] ? [] : {
[index in keyof InputArrays]: InputArrays[index] extends readonly (infer InputElement)[] ? InputElement : never;
}[];