Recurring fuction which reruns if a certain condition is not met in a loop-CodePudding

I need UsernameFn recursively called (cc later lines) until the conditional loop within which it is called becomes untrue. If I place the loop outside UsernameFn function entirely, console says Username is undefined, even though the var Username is declared globally. What am I supposed to do?

[It says to add more detail. I have no more detail. It says to add more detail. I have no more detail. It says to add more detail. I have no more detail. It says to add more detail. I have no more detail. ]

// dataset for username 

const alpha = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'];
const num = ['1', '2', '3', '4', '5', '6', '7', '8', '9', '0'];
var counter = 0;
var Username;

// determine random length of the username
var UNlength = Math.random() * 11;
UNlength = UNlength.toFixed(0);

function UsernameFn() {
  // generate random nums as pickers
  var PickerN = Math.random() * 10;
  PickerN = PickerN.toFixed(0);
  var PickerA = Math.random() * 26;
  PickerA = PickerA.toFixed(0);
  var PickerG = Math.random() * 10;
  PickerG = PickerG.toFixed(0);

  // Pickers for the first character in "Username"
  var PickerUN = Math.random() * 10;
  PickerUN = PickerUN.toFixed(0);
  var PickerUA = Math.random() * 26;
  PickerUA = PickerUA.toFixed(0);
  var PickerUG = Math.random() * 10;
  PickerUG = PickerUG.toFixed(0);

  // choose randomly btw num and alpha. If Math.random 
  // is an even num, option = alpha. If odd num, option = num
  if (PickerG % 2 == 0) {
    var Chosen = num[PickerN];
  } else {
    var Chosen = alpha[PickerA];
  }

  if (PickerUG % 2 == 0) {
    var Username = num[PickerUN];
  } else {
    var Username = alpha[PickerUA];
  }

  //append each new choice to a string of previous choices
  //when string = UNlength <= 10 chosen ranbdomly above, stop recursion.
  // 'Username' declaration outside scope to allow loop access
  Username = String(Username)   String(Chosen);
  return Username;

  counter  = 1;
  do {
    UsernameFn()
  } while (Username.length <= UNlength.length);
}

CodePudding user response：

The loop should be outside the function. Then you need to concatenate the returned value to the Username variable.

Also, UNlength.length should just be UNlength.

// dataset for username 

const alpha = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'];
const num = ['1', '2', '3', '4', '5', '6', '7', '8', '9', '0'];
var counter = 0;
var Username = '';

// determine random length of the username
var UNlength = Math.random() * 11;
UNlength = UNlength.toFixed(0);

do {
  Username  = UsernameFn();
  counter  ;
} while (Username.length <= UNlength);

console.log(Username, counter);

function UsernameFn() {
  // generate random nums as pickers
  var PickerN = Math.random() * 10;
  PickerN = PickerN.toFixed(0);
  var PickerA = Math.random() * 26;
  PickerA = PickerA.toFixed(0);
  var PickerG = Math.random() * 10;
  PickerG = PickerG.toFixed(0);

  // Pickers for the first character in "Username"
  var PickerUN = Math.random() * 10;
  PickerUN = PickerUN.toFixed(0);
  var PickerUA = Math.random() * 26;
  PickerUA = PickerUA.toFixed(0);
  var PickerUG = Math.random() * 10;
  PickerUG = PickerUG.toFixed(0);

  // choose randomly btw num and alpha. If Math.random 
  // is an even num, option = alpha. If odd num, option = num
  if (PickerG % 2 == 0) {
    var Chosen = num[PickerN];
  } else {
    var Chosen = alpha[PickerA];
  }

  if (PickerUG % 2 == 0) {
    var Username = num[PickerUN];
  } else {
    var Username = alpha[PickerUA];
  }

  //append each new choice to a string of previous choices
  //when string = UNlength <= 10 chosen ranbdomly above, stop recursion.
  // 'Username' declaration outside scope to allow loop access
  Username = String(Username)   String(Chosen);
  return Username;
}