在另一个函数中调用一个函数

Question

I am trying to call the getWinner function inside the playFiveTimes function and every time I try to test my code it gives me an error that says: "playerMove undefined" or if I try and type "rock" it says that is undefined as well. I am completely lost at this point. Any help would be appreciated.

'use strict';

function getInput() {
  console.log("Please choose either 'rock', 'paper', or 'scissors'.")
  return prompt();
}

function randomPlay() {
  var randomNumber = Math.random();
  if (randomNumber < 0.33) {
    return "rock";
  } else if (randomNumber < 0.66) {
    return "paper";
  } else {
    return "scissors";
  }
}

function getPlayerMove(move) {
  if (!move) {
    move = getInput();
  }
  return move;
}

function getComputerMove(move) {
  if (!move) {
    move = getInput();
  }
  return move;
}

function getWinner(playerMove, computerMove) {
  var winner;
  if (playerMove === computerMove) {
    return ("It's a tie!");
  } else if (playerMove === "rock") {
    if (computerMove === "paper") {
      return "paper wins";
    } else {
      return "rock wins";
    }
  } else if (playerMove === "paper") {
    if (computerMove === "rock") {
      return "paper wins";
    } else {
      return "scissors wins";
    }
  } else if (playerMove === "scissors") {
    if (computerMove === "paper") {
      return "scissors wins";
    } else {
      return "rock wins";
    }
  }
  return winner;
}

function playToFive() {
  console.log("Let's play Rock, Paper, Scissors");
  var playerWins = 0;
  var computerWins = 0;
  // Write code that plays 'Rock, Paper, Scissors' until either the player or the computer has won five times.
  while ((playerWins < 5) && (computerWins < 5)) {
    getWinner();
    if (playerWins) {
      playerWins += 1
    } else {
      computerWins += 1
    }
  }

  console.log("Player chose " + playerMove + " while computer chose " + computerMove);
  console.log("The score is currently " + playerWins + " to " + computerWins + "\n");
  return [playerWins, computerWins];
}
console.log(playToFive());

Answer 1

You are calling the function with no parameters. It expects two parameters, as you specified, function getWinner(playerMove, computerMove) {...} . So, supply the two parameters in the function call, ie getWinner('rock', 'paper') . The program only does what you tell it. You cannot call getWinner() with no parameters and expect a result.

Second, there is no use for the variable winner inside the same function. You literally do not use it at all except to return it if there is no winner. That's counterintuitive.

Third, you never define playerMove and computerMove in the playToFive() function, and you never assign them a value.

Debugging and desk-checking your code helps lead you to these facts pretty easily.

Answer 2

Your script is crashing on this line:

console.log("Player chose " + playerMove + " while computer chose " + computerMove);

inside your playToFive() function because playerMove and computerMove variables are undefined but you're trying to cast it to string. You need to define your variables before using it.

This is the reason for the "playerMove undefined" error but also you should check your program's logic as it was said before by Brett and Ivern

Answer 3

I thing that the BIGGEST mistake is doing function inside function, try:

if (playerMove === "rock") | (computerMove === "paper") { return "paper wins"; }

I thing that might work. The "|" means and, you probably know that, but just I am not sure