missing ; after for-loop initializer

Question

var nodeWordsString = document.getElementById("nodeWordsTextArea").value.trim();
    var nodeWordsStringArray=nodeWordsString.split(" ");
    var strLength = nodeWordsStringArray.length;
    for(int i = 0; i < nodeWordsStringArray.length; i++)----->******
    {
        for(int j = 0; j < nodeWordsStringArray.length; j++)
        {
            if(nodeWordsStringArray(i) == nodeWordsStringArray(j))
            {
                alert("Node duplication occurred at:"+nodeWordsStringArray(i));
                return false;
                //break;
            }
        }
    }

**showing error like missing ; after for-loop initializer in java script console(firebug). please help me.

Answer 1

This is javascript, but you're using int in your loop declaration? Try replacing those with var instead.

Answer 2

In my case, the error was caused by using let in the loop. Old browsers like Firefox 38 doesn't support let.

Replacing let by var solved the issue.

Answer 3

Change int i and int j to var i and var j.

Answer 4

If you are here in 2016, maybe you are trying to use a let declaration outside strict mode in a browser that does not yet support it. Replace it with var or add 'use strict;' to the top of your function.