making a range function in javascript
<p>I am trying to make a function in javascript that returns an array from range(start,end) and im supposed to make an optional argument that defaults to one when it is undefined. I can get the function to work when I provide all the arguments but returns an empty array when I only pass two arguments. Here is the question:</p>
<blockquote>
<p>Write a range function that takes two arguments, start and end, and returns an array containing all the numbers from start up to (and including) end.</p>
<p>Next, write a sum function that takes an array of numbers and returns the sum of these numbers. Run the previous program and see whether it does indeed return 55.</p>
<p>As a bonus assignment, modify your range function to take an optional third argument that indicates the “step” value used to build up the array. If no step is given, the array elements go up by increments of one, corresponding to the old behavior. The function call range(1, 10, 2) should return [1, 3, 5, 7, 9]. Make sure it also works with negative step values so that range(5, 2, -1) produces [5, 4, 3, 2].</p>
</blockquote>
<p>And here is my code:</p>
<pre><code>function range(start, end, increment){
var array = [];
var current = start;
var counter;
if (increment == undefined){
    counter = 1;
}

else {
    counter = increment;
}

if (increment &gt; 0){
    while(current &lt;= end){
        array.push(current);
        current += counter;
    }
}
  
else if (increment &lt; 0){
    while(current &gt;= end){
        array.push(current);
        current += counter;
        
    }
}

return array;
}
</code></pre>
<p>can someone explain why its breaking? I know some c# and I used to being able to jump into the debugger in visual studio when something goes wrong unlike javascript.</p>