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JavaScript

Posted by Andrew Scherer
Andrew Scherer
3,942 Points

Robot Maze Issue

Seem to be getting this error: "Uncaught TypeError: undefined is not a function"

for my code on robot.html with the line:

m.setStart(1,1,"north");

I believe it is because north hasn't been defined? I have deleted all my code, re-did it all again from the start of the video and still received the same error. I am also not seeing the drop list of values for m similar to what the video shows.

Here is my maze.js code.

"use strict";

function Maze(width,height) {
    this.width = width;
    this.height = height;
    this.startX             = null;
    this.startY             = null;
    this.startOrientation   = null;
    this.endX               = null;
    this.endY               = null;

}

Maze.prototype.setStart = function (x, y, orientation) {
    this.startX = x;
    this.startY = y;
    this.startOrientation = orientation;
}

Maze.prototype.setEnd = function (x, y) {
    this.endX = x;
    this.endY = y;


}

Here is the robot.html code:

<!DOCTYPE html>
<head>

<script type="text/javascript" src="js/robot.js"></script>
<script type="text/javascript" src="js/maze.js"></script>
<script type="text/javascript" src="js/mazespace.js"></script>

<script>
    m = new Maze(7,5);
    m.setStart(1,1,"north");
    m.setEnd(7,1);
    </script>

</head>

<body>

<div id="page">
    Loading....
    </div>
    </body>
    </html>
Andrew Scherer
Andrew Scherer
3,942 Points

Hmm when I open in firefox it gives a different error in the console "TypeError: m.setStart is not a function"

But when I use firebug console, no error.

Maybe it just depends on what browser console I am using, and there may be no error at all?

Andrew Scherer
Andrew Scherer
3,942 Points

OK nevermind, the problem is the way I had my files saved. It was calling on an old version of maze.js instead of the one I was actively writing to. Oops.

1 Answer

Aaron Graham
Aaron Graham
18,033 Points
Aaron Graham
Aaron Graham
18,033 Points

This is purely a guess, but I wonder if it has to do with your use of "use strict" and your declaration of "m" without using var. Like this:

m = new Maze(7, 5);

Instead of:

var m = new Maze(7, 5);

My understanding of "use strict" is that it only applies to the file it is declared in, but I wonder if, since it is used with the declaration of Maze, instances of Maze also fall under the "use strict" declaration. Again, just a guess.

Edit: just saw your comment... Never mind :-)