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JavaScript error (Uncaught SyntaxError: Unexpected end of input)

I have some JavaScript code that works in FireFox but not in Chrome or IE.

In the Chrome JS Console I get the follow error:

"Uncaught SyntaxError: Unexpected end of input".

The JavaScript code I am using is:

<script>
 $(function() {
 $("#mewlyDiagnosed").hover(function() {
    $("#mewlyDiagnosed").animate({'height': '237px', 'top': "-75px"});
 }, function() {
    $("#mewlyDiagnosed").animate({'height': '162px', 'top': "0px"});
 });
</script>

It says the error is on the last line which is });

I know that Chrome's V8, for a DELETE on the server if the response was a 200 success instead of a 204 success - no response I would get this error as well. Just heads up in case anyone is getting this as well.

S
SLaks

Add a second });.

When properly indented, your code reads

$(function() {
    $("#mewlyDiagnosed").hover(function() {
        $("#mewlyDiagnosed").animate({'height': '237px', 'top': "-75px"});
    }, function() {
        $("#mewlyDiagnosed").animate({'height': '162px', 'top': "0px"});
    });
MISSING!

You never closed the outer $(function() {.


The lesson is, always indent your code (and indent it correctly).
The lesson is, always use good editor with good plugins, which can detect parentheses pairing, highlight it or even repair problems.
@HeyWatchThis You might try Syntastic for Vim.
I use neomake for vim/neovim, configured to run jshint every time I save a JavaScript file. If I have syntax errors, I'll see warning/error symbols in vim's/neovim's gutter. When I put my cursor on that line, the vim/neovim command line will show a message saying what the error is.
missing that simple }); just saved me 1 hour of debugging. many thanks @SLaks
f
falsarella

In my case, I was trying to parse an empty JSON:

JSON.parse(stringifiedJSON);

In other words, what happened was the following:

JSON.parse("");

This, unfortunatly, includes $.parseJSON of jquery 1.11.2
f
falsarella

http://jsbeautifier.org/ is helpful to indent your minified JS code.

Also, with Google Chrome you can use "pretty print". See the example screenshot below showing jquery.min.js from Stack Overflow nicely indented right from my browser :)

https://i.stack.imgur.com/2906e.png


S
Sebastian Kaczmarek

Formatting your code a bit, you have only closed the inner hover function. You have not closed the outer parts, marked below:

$(// missing closing)
 function() { // missing closing }
     $("#mewlyDiagnosed").hover(
        function() {
            $("#mewlyDiagnosed").animate({'height': '237px', 'top': "-75px"});
        }, 
        function() {
            $("#mewlyDiagnosed").animate({'height': '162px', 'top': "0px"});
        });

S
Sebastian Kaczmarek

In my case, it was caused by a missing (0) in javascript:void(0) in an anchor.


Same issue: but, I had javascript:void(0 missing a )
Y
Yëco

In my case, it ended up being a simple double quote issue in my bookmarklet, remember only use single quotes on bookmarklets. Just in case this helps someone.


Thanks a million! I never knew that this would be an issue
Glad it helped.
S
Sebastian Kaczmarek

This error is mainly caused by empty returned ajax calls, when trying to parse an empty JSON.

To solve this test if the returned data is empty

$.ajax({
    url: url,
    type: "get",
    dataType: "json",
    success: function (response) {

        if(response.data.length == 0){
            // EMPTY
        }else{
            var obj =jQuery.parseJSON(response.data);
            console.log(obj);
        }
    }
});

f
falsarella

I got this error when I was trying to write a javascript bookmarklet. I couldn't figure out what was causing it. But eventually I tried URL encoding the bookmarklet, via the following website: http://mrcoles.com/bookmarklet/ and then the error went away, so it must have been a problem with certain characters in the javascript code being interpreted as special URL control characters.


I had a // comment in my js, which commented out a bit more than I wanted since pasting it into the url of the bookmarklet made the whole code a one-liner and the // was in the middle of the code.
Removing comments fixed it for me as well.
J
Jack Hales

I got this since I had a comment in a file I was adding to my JS, really awkward reason to what was going on - though when clicking on the VM file that's pre-rendered and catches the error, you'll find out what exactly the error was, in my case it was simply uncommenting some code I was using.


I had the same issue, sometimes ftp transfer mess up file's lines, and single line comments may include afterward lines in their line
j
justanotherguy

I also got this error pointing to the end of the last script block on a page, only to realize the error was actually from clicking on an element with a onclick="pagename" instead of onclick="window.location='pagename'". It's not always a missing bracket!


P
Petr

I think it could be almost any javascript error/typing error in your application. I tried to delete one file content after another and finally found the typing error.


I am getting this error on the second and sunsequent calls. The first call works fine but thereafter i get the error and it points to line one of the html. Unhelpful. I wrote a program to check all brces, brackets and quotes and all are balanced. The code is quite complex maybe - and there is a lot of it. Any other ideas please?