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Stack Overflow After 15 Recursions with Javascript Class Function

I have the following code sample to illustrate my point. When I load this in IE8 on Vista I get the error "Stack Overfow at line:16"

If I recurse using a top level function (outside of the testClass object) I can recurse millions of times without a stack overflow.

Why is this happening? Ultimately I just implemented a Function Que instead of using recursion, but just doesn't make sense to me, and I'd like to understand the cause.

-- code --

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN">
<html>
    <head>
        <title>Recusion Test</title>
        <body>
        </body>

        <script type="text/javascript">

            function testClass() {
                this.x = 15;
                this.recurse = function() {
                    this.x--;
                    this.recurse();
                }
            }

            var wtf = new testClass();
                wtf.recurse();

            alert('done');
        </script>
    </head>
</html>
Solution

  • There is no terminating condition for your recursive statement therefore it will run forever.

    It appears that you want...

    
            function testClass() {
                this.x = 15;
                this.recurse = function() {
                    if (this.x--)
                        this.recurse();
                }
            }

            var wtf = new testClass();
                wtf.recurse();

            alert('done');