@veremenko/lotide/flatten.js

Lodash alike library

// //Emojis
// const pass = String.fromCodePoint(0x1F600);
// const fale = String.fromCodePoint(0x1F47A);

// // Functions implementation
// const assertArraysEqual = function(arr1, arr2) {
//   eqArrays(arr1, arr2);
//   if (eqArrays(arr1, arr2)) {
//     console.log(pass, pass, pass, `Arrays are equal`);
//   } else {
//     console.log(fale, fale, fale, `Arrays are different`);
//   }
// };

// const eqArrays = function(arr1, arr2) {
//   if (arr1.length !== arr2.length) {
//     //console.log('Unequal length', false);
//     return false;
//   } else {
//     let similarElements = true;
//     for (let i = 0; i < arr2.length; i++) {
//       if (arr1[i] === arr2[i]) {
//         //console.log(arr1[i], arr2[i]);
//         //console.log(`${i} different elements index`);
          
//       } else {
//         similarElements = false;
//         //console.log('scope', similarElements);
//         return similarElements;

//       }
//     }
//     if (similarElements) {
//       //console.log('Equal arrays', similarElements);
//     }
//     return similarElements;
//   }
  
// };

const flatten2 = function(arrayToFlatten) {
  return arrayToFlatten.flat();
};

const flatten = function(arrayToFlatten) {

  let flatArray = [];

  for (let i = 0; i < arrayToFlatten.length; i++) {
    //console.log(Array.isArray(arrayToFlatten[i]));
    if (Array.isArray(arrayToFlatten[i])) {
      for (let j = 0; j < arrayToFlatten[i].length; j++) {
        //console.log(arrayToFlatten[i][j]);
        flatArray.push(arrayToFlatten[i][j]);
      }
    } else {
      flatArray.push(arrayToFlatten[i]);
    }

    
  }

  return flatArray;
};

module.exports = {
  flatten: flatten, 
  flatten2: flatten2
}

// const testArray = [1, 2, [3, 4], 5, [6]];

// console.log(flatten(testArray));
// console.log(flatten2(testArray));