Javascript - indexOf is not funciton

Question

I have this event ...

   <textarea id="chat"> </textarea>
   <button type="button" onclick="play_song();">talk</button>

... causing the following function:

   var input = function() {
           var chat = document.getElementById("chat").value.split(" ");
           return chat && console.log(chat);
        }

then there function:

   function setIntersection(a, b) {

      var result = [];

      for (var i = 0; i < a.length; i++) {
         if (b.indexOf(a[i]) !== -1 && result.indexOf(a[i]) === -1) {
            result.push(a[i]);
         }
      }
    return result;
   }

a prototype function:

   Song.prototype.lyricsIntersect = function(input) {


      var bestSong = null;
      var bestCount = -Infinity;

      for (var i in songs) {
        var currentCount = setIntersection(songs[i].lyrics, input).length;

    if (currentCount > bestCount) {
        bestSong = songs[i];
        bestCount = currentCount;
    }
}

return bestSong && bestSong.name;
}

The code ends here:

   function play_song() {

    var id = Song.prototype.lyricsIntersect(input);
    var element = document.getElementById(id);
    element.play();
}

but console.logreturns:Uncaught TypeError: b.indexOf is not a function

If I test var input = ["one", "two"];, however, I get the intersection done on the code, depending on input.

What am I missing?

Answer 1

var currentCount = setIntersection(songs[i].lyrics, input).length;

it should be

var currentCount = setIntersection(songs[i].lyrics, input()).length;

it also depends on the fact that the input is adjusted as follows

var input = function() {
   var chat = document.getElementById("chat").value.split(" ");
   return chat;
}

Answer 2

What am I missing?

Here you declare the input as global and assign the function:

var input = function() {
    var chat = document.getElementById("chat").value.split(" ");
    return chat && console.log(chat);
}

I prefer function declarations, but each is their own.

Here you pass the input as a parameter to Song.prototype.lyricsIntersect

var id = Song.prototype.lyricsIntersect(input);

:

Song.prototype.lyricsIntersect = function(input) {

setIninterection:

    var currentCount = setIntersection(songs[i].lyrics, input).length;

setIntersection b:

function setIntersection(a, b) {

:

     if (b.indexOf(a[i]) !== -1 && result.indexOf(a[i]) === -1) {

Answer 3

indexOf Array b Array. b.

doc Array.prototype.indexOf()

EDIT:

, b input. , input - Array. , .. input - , Array.

Answer 4

, ( ) ( ). indexOf:

typeof [].indexOf // "function"

typeof ''.indexOf // "function"

, , indexOf.