To get a truthy condition(array) from a nested array, for now the function returns boolean value tru-CodePudding

The checkWin function returns true when an array which are index numbers have a speicified symbol on another Array's indexes. How to retrieve the "cond"(array) which results in true from the nested winConditions array ?

Symbols get populated using the click event listener.

The expected result should be, if .some(cond) becomes true then return that cond for eg. if symbol "X" is present on [0, 1, 2] then return this array

let testArray = Array(9).fill("") 
 
  const winConditions = [
    [0, 1, 2],
    [3, 4, 5],
    [6, 7, 8],
    [0, 3, 6],
    [1, 4, 7],
    [2, 5, 8],
    [0, 4, 8],
    [2, 4, 6],
  ];

  let xValue = "X";
  let oValue = "O";

function checkWin(value, array) {
    return winConditions.some((cond) =>
        cond.every((index) => array[index] == value));
}

console.log(checkWin(xValue, testArray));
console.log(checkWin(oValue, testArray));

CodePudding user response：

You can use .find() instead of .some(), this will return the first array that the .every() callback returns true for. You can use this array to determine if there was a win or not for a particular player:

const testArray = Array(9).fill("");
testArray[3] = testArray[4] = testArray[5] = "O"; // test winning position
const winConditions = [
  [0, 1, 2],
  [3, 4, 5],
  [6, 7, 8],
  [0, 3, 6],
  [1, 4, 7],
  [2, 5, 8],
  [0, 4, 8],
  [2, 4, 6],
];

const xValue = "X";
const oValue = "O";

function getWinPos(value, array) {
  return winConditions.find((cond) =>
    cond.every((index) => array[index] == value)
  );
}

const xWinPos = getWinPos(xValue, testArray);
const oWinPos = getWinPos(oValue, testArray);

if(xWinPos) { // found a winning position row/col/diag for "X"
  console.log(xWinPos);
} else if(oWinPos) { // found a winning row/col/diag for "O"
  console.log(oWinPos);
}