hkt-toolbelt/natural-number-theory/is-valid-sudoku.d.ts

Functional and composable type utilities

import { $, Boolean, Conditional, Function, Kind, List, Matrix } from '..';
type HasAllUniqueElements = $<Kind.Pipe, [
    List.Duplicates,
    List.Length,
    $<Conditional.Equals, 0>
]>;
type HasAllUniqueElementsExcludingZero = $<Kind.Pipe, [
    $<List.Filter, $<Conditional.NotEquals, 0>>,
    HasAllUniqueElements
]>;
type LengthIsNine = $<Kind.Pipe, [List.Length, $<Conditional.Equals, 9>]>;
type IsValidSet = $<Kind.Pipe, [
    $<Kind.Juxt, [HasAllUniqueElementsExcludingZero, LengthIsNine]>,
    Boolean.AndAll
]>;
type GetRows = Function.Identity;
type GetColumns = Matrix.Columns;
type GetBoxes = $<Kind.Pipe, [
    $<$<Matrix.Chunk, 3>, 3>,
    $<List.Map, $<List.FlattenN, 1>>
]>;
/**
 * A type-level function that checks if a given 2D array is a valid Sudoku
 * puzzle.
 *
 * A Sudoku puzzle is a 9x9 grid of numbers where each row, column, and 3x3 box
 * contains the numbers 1-9 exactly once.
 *
 * The number 0 represents an uncompleted cell, which is considered valid.
 *
 * @template T - The 2D array to check.
 */
export type IsValidSudoku = $<Kind.Pipe, [
    $<Kind.Juxt, [GetRows, GetColumns, GetBoxes]>,
    $<List.FlattenN, 1>,
    $<List.Map, IsValidSet>,
    Boolean.AndAll
]>;
export {};