Recently, I ran some of my JavaScript code through Crockford&#39;s [JSLint][1], and it gave the following error:

&gt; Problem at line 1 character 1: Missing &quot;use strict&quot; statement.

Doing some searching, I realized that some people add `&quot;use strict&quot;;` into their JavaScript code. Once I added the statement, the error stopped appearing. Unfortunately, Google did not reveal much of the history behind this string statement. Certainly it must have something to do with how the JavaScript is interpreted by the browser, but I have no idea what the effect would be.

So what is `&quot;use strict&quot;;` all about, what does it imply, and is it still relevant?

Do any of the current browsers respond to the `&quot;use strict&quot;;` string or is it for future use?

  [1]: http://www.jslint.com/

What does &quot;use strict&quot; do in JavaScript, and what is the reasoning behind it?

I&#39;m trying to get my Javascript code 100% JSLint clean.

I&#39;ve got some JS code that I&#39;ve lifted from elsewhere to create a UUID. That code has the following line:

    s[16] = hexDigits.substr((s[16] &amp; 0x3) | 0x8, 1);

This line incites JSLint to generate two error messages:

    1) Unexpected use of &#39;&amp;&#39;
    2) Unexpected use of &#39;|&#39;

I don&#39;t understand why -- I&#39;d appreciate counsel regarding how to recode to eliminate the error message.

JSLint reports unexpected use of &#39;&amp;&#39; and &#39;|&#39; -- I&#39;d like to clean this

&gt; **Possible Duplicate:**  
&gt; [JSLint: was used before it was defined](https://stackoverflow.com/questions/9621162/jslint-was-used-before-it-was-defined)  

&lt;!-- End of automatically inserted text --&gt;

I run `JSlint` and saw errors like that:

&lt;pre&gt;&#39;foo&#39; is not defined.
var x = foo();&lt;/pre&gt;

`foo` is a function defined in another `JavaScript` file `foo.js`. As I understand there is no &quot;import / require&quot; directives in `JavaScript` to reference the `foo` function defined in another source file.

How can I fix this error repoted by `JSlint`? 


How to fix &quot;foo is not defined&quot; error reported by JSlint?

Consider the following code:

	for (var i=0; i&lt;100; i++) {
		// your code here
	}
	// some other code here
	for (var i=0; i&lt;500; i++) {
		// custom code here
	}

Any decent lint tool (jslint, jshint or built in IDE) will tell warning - `duplicate declaration of variable i`. This can be solved by using variable with another name (`k`, `j`) or moving declaration to the top:

	var i; // iterator
	for (i=0; i&lt;100; i++) {}
	for (i=0; i&lt;500; i++) {}

I am not fond of both variants - I don&#39;t make declarations at the top usually (and even if I did I wouldn&#39;t want see there helper variables - `i`, `j`, `k`) and really nothing bad is going on in those examples to change variables&#39; names for.

Though I do want a huge warning in case I write something like this:

	for (var i=0; i&lt;100; i++) {
		for (var i=0; i&lt;500; i++) {} // now that&#39;s bad
	}

What&#39;s your approach to such cases?

Dealing with duplicate declaration warning for loop variables

I am writing JS UT for my NodeJS code. I am using [Chai][1] as the assertion library, and I prefer the *should* syntax. I also use *jslint* to check the JS file syntax, even the JS files for UT.

Now I have a problem with *jslint* and *Chai*. In *Chai*, you can use:

    myvalue.should.be.true;

But *jslint* give me:

    #1 Expected an assignment or function call and instead saw an expression.

I know *jslint* comes with many options, but I just cannot find the right one to turn off this check.

  [1]: http://chaijs.com/

How to get &quot;should.be.false&quot; syntax pass jslint?

I used [JSLint][1] on a JavaScript file of mine. It threw the error:

    for( ind in evtListeners ) {

&gt; Problem at line 41 character 9: The body of a for in should be
&gt; wrapped in an if statement to filter unwanted 
&gt; properties from the prototype.

What does this mean?


  [1]: http://www.jslint.com/

What does the JSLint error &#39;body of a for in should be wrapped in an if statement&#39; mean?

I include the statement:

    &quot;use strict&quot;;

at the beginning of most of my Javascript files.

JSLint has never before warned about this. But now it is, saying:

&gt;Use the function form of &quot;use strict&quot;.

Does anyone know what the &quot;function form&quot; would be?

JSLint is suddenly reporting: Use the function form of &quot;use strict&quot;

What is the difference between this constructor-based syntax for creating an object:

    person = new Object()

...and this literal syntax:

    person = {
    	property1 : &quot;Hello&quot;
    };

It appears that both do the same thing, although JSLint prefers you use object literal notation.

Which one is better and why?

What is the difference between `new Object()` and object literal notation?

Most of the tutorials that I&#39;ve read on arrays in JavaScript (including [w3schools][1] and [devguru][2]) suggest that you can initialize an array with a certain length by passing an integer to the Array constructor using the `var test = new Array(4);` syntax.

After using this syntax liberally in my js files, I ran one of the files through [jsLint][3], and it freaked out:

&gt; Error: Problem at line 1 character 22: Expected &#39;)&#39; and instead saw &#39;4&#39;.&lt;br&gt;
&gt; var test = new Array(4);&lt;br&gt;
&gt; Problem at line 1 character 23: Expected &#39;;&#39; and instead saw &#39;)&#39;.&lt;br&gt;
&gt; var test = new Array(4);&lt;br&gt;
&gt; Problem at line 1 character 23: Expected an identifier and instead saw &#39;)&#39;.

After reading through [jsLint&#39;s explanation of its behavior][4], it looks like jsLint doesn&#39;t really like the `new Array()` syntax, and instead prefers `[]` when declaring arrays.

So I have a couple questions:

First, why?  Am I running any risk by using the `new Array()` syntax instead?  Are there browser incompatibilities that I should be aware of?

And second, if I switch to the square bracket syntax, is there any way to declare an array and set its length all on one line, or do I have to do something like this:

    var test = [];
    test.length = 4;


  [1]: http://www.w3schools.com/js/js_obj_array.asp
  [2]: http://www.devguru.com/technologies/ecmascript/quickref/array.html
  [3]: http://www.jslint.com/
  [4]: http://www.jslint.com/lint.html

How to initialize an array&#39;s length in JavaScript?

I have a very long regular expression, which I wish to split into multiple lines in my JavaScript code to keep each line length 80 characters according to JSLint rules. It&#39;s just better for reading, I think.
Here&#39;s pattern sample:

    var pattern = /^(([^&lt;&gt;()[\]\\.,;:\s@\&quot;]+(\.[^&lt;&gt;()[\]\\.,;:\s@\&quot;]+)*)|(\&quot;.+\&quot;))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;

How to split a long regular expression into multiple lines in JavaScript?

I&#39;m a pretty new Vim user and I&#39;ve found that its learning curve is quite steep (at least for me). I just installed [this vim script][1] for JavaScriptLint error checking, which shows errors in vim&#39;s quickfix window once I save a buffer.

However, I don&#39;t know what to do next.. How do I &#39;scroll&#39; through all the errors? How do I close the quickfix &#39;window&#39;? How do I get it to check for errors after I&#39;ve made changes to my code?

I&#39;ve looked at the vim quickfix docs but the amount of commands are overwhelming and I can&#39;t seem to find what I want. Any help would be appreciated.

A side question: is there any way to have javascriptlint check for js errors for code residing in a .html file?



  [1]: https://stackoverflow.com/questions/473478/vim-jslint/628872#628872

How do you use vim&#39;s quickfix feature?

What ***is*** the best practice for that then?

Jslint explains that it &quot;adds confusion&quot;. I don&#39;t see it really...


EDIT: The code, as requested:

      var all,l,elements,e;
      all = inElement.getElementsByTagName(&#39;*&#39;);
      l = all.length;
      elements = [];
      for (e = 0; e &lt; l; (e++))
      {
        if (findIn)
        {
            if (all[e].className.indexOf(className) &gt; 0)
            {
                elements[elements.length] = all[e];
            }
        } else {
            if (all[e].className === className)
            {
                elements[elements.length] = all[e];
            }
        }
      }

The &quot;unexpected ++&quot; error in jslint

I ran  JSLint on this JavaScript code and it said: 

&gt;Problem at line 32 character 30: Missing radix parameter.

This is the code in question:

    imageIndex = parseInt(id.substring(id.length - 1))-1;

What is wrong here?

JSLint says &quot;missing radix parameter&quot;

### Original Question:

[JSHint][1] complains when my JavaScript calls a function that is defined further down the page than the call to it. However, my page is for a game, and no functions are called until the whole thing has downloaded. So why does the order functions appear in my code matter?


### EDIT: I think I may have found the answer.
http://www.adequatelygood.com/2010/2/JavaScript-Scoping-and-Hoisting

I am groaning inside. Looks like I need to spend ANOTHER day re-ordering six thousand lines of code. The learning curve with javascript is not steep at all, but it is very loooooong.


  [1]: http://www.jshint.com/

JavaScript function order: why does it matter?

There is a [JSLint](http://www.jslint.com) option, one of The Good Parts in fact, that &quot;[requires] parens around immediate invocations,&quot; meaning that the construction

    (function () {
      
      // ...
      
    })();

would instead need to be written as

    (function () {
      
      // ...
      
    }());

My question is this -- can anyone explain why this second form might be considered better?  Is it more resilient?  Less error-prone?  What advantage does it have over the first form?

---

Since asking this question, I have come to understand the importance of having a clear visual distinction between function values and the values of functions.  Consider the case where the result of immediate invocation is the right-hand side of an assignment expression:

    var someVar = (function () {
      
      // ...
      
    }());

Though the outermost parentheses are syntactically unnecessary, the opening parenthesis gives an up-front indication that the value being assigned is &lt;em&gt;not&lt;/em&gt; the function itself but rather the result of the function being invoked.

This is similar to Crockford&#39;s advice regarding capitalization of constructor functions -- it is meant to serve as a visual cue to anyone looking at the source code.


Immediate function invocation syntax

&gt; I think  this may be a duplicate of https://stackoverflow.com/questions/6300937/strict-violation-using-this-keyword-and-revealing-module-pattern



I have this code:

    function gotoPage(s){
        if(s&lt;=this.d&amp;&amp;s&gt;0){this.g=s; this.page((s-1)*this.p.size);}
    }

    function pageChange(event, sorter) {
        var dd = event.currentTarget;
        gotoPage.call(sorter, dd[dd.selectedIndex].value);
    }

And JSHINT (JSLINT) is complaining.  It says &quot;Strict violation.&quot; for the highlighted line: 

![enter image description here][1]


Is my use of `Function.call()` and then referencing the instance, somehow inappropriate? 

Is this considered to be bad style?

  [1]: http://i.imgur.com/1SIfX.png

Why is JSHINT complaining that this is a strict violation?

Hi I have the 3 javascript files.

 * jquery.js
 * utility.js
 * file1.js


In file1.js I have 

    jQuery.noConflict()
    jQuery(document).ready(function($) { 
     // ....
    });


I get an error &#39;jQuery&#39; was used before it was defined. 
and &#39;document&#39; was used before it was defined. 


How do I safely get rid of this warning.  

If I do 

    var document = document || {}; 

then in my utility.js if it is used, it would be null in IE and ok in firefox. 

What is the best solution to this?


JSLint: was used before it was defined

Recently I was running some of my code through JSLint when I came up with this error. The thing I think is funny about this error though is that it automatically assumes that all == should be ===. 

Does that really make any sense? I could see a lot of instances that you would not want to compare type, and I am worried that this could actually cause problems.

The word &quot;Expected&quot; would imply that this should be done EVERY time.....That is what does not make sense to me.


JSLint Expected &#39;===&#39; and instead saw &#39;==&#39;

I am currently validating my JavaScript against JSLint and making progress on, it&#39;s assisting me to write better JavaScript - in particular in working with the Jquery library.

I have now come across **JSHint**, a fork of **JSLint**.  
So I am wondering for web applications, which are very much JavaScript was driven, which is the better or most applicable validation tool to work against:  

- JSLint or JSHint?  

I want to decide now on a validation mechanism and moving forward, use this for client side validation.

And Difference between jshint and jslint? Please explain in single javascript example.

Links:

 1. **jshint**-    http://www.jshint.com/
   
 2. **jslint**-    http://jslint.com/



Should I use JSLint or JSHint JavaScript validation?

In my project we have some global variables that work as containers:

    MyProject.MyFreature.someFunction = function() { ... }

So then I use that script across the site and JSLint / JSHint complains about that:

&gt; &#39;MyProject&#39; is not defined

I know that I can go to every JavaScript file and add the comment `/*global MyProject*/` on top of it. But I&#39;m looking a way to define that comment in some sort of config file so I don&#39;t have to go file by file adding this comment.

Some kind on option in the `config/jshint.yml` would be nice.

How to tell JSLint / JSHint what global variables are already defined

I notice that in CoffeeScript, if I define a function using:

    a = (c) -&gt; c=1

I can only get the **function expression**:

    var a;
    a = function(c) {
        return c = 1;
    };

But, personally I often use **function declaration**,for example:

    function a(c) {
        return c = 1;
    }

I do use the first form, but I&#39;m wondering if there is a way in CoffeeScript generating a function declaration. If there is no such way, I would like to know why CoffeeScript avoid doing this. I don&#39;t think JSLint would holler an error for declaration, as long as the function is declared at the top of the scope.

Function declaration in CoffeeScript

what can I do if JSLint complains about &quot;i&quot; being an unused variable in such a scenario:

    var items = &quot;&lt;option selected&gt;&lt;/option&gt;&quot;;
    $.each(data, function (i, item) {
        items += &quot;&lt;option value=&#39;&quot; + item.Value + &quot;&#39;&gt;&quot; + item.Text + &quot;&lt;/option&gt;&quot;;
    });

(i, item) is the required order of parameters and I&#39;m only using &quot;item&quot;. 

Is there any other solution than tolerating unused variables or rewriting the $.each to use the index, both solutions which I would prefer not to do?

Thanks in advance.

Update: I appreciate all the suggestions but this code is simply an example to show you what I mean and I&#39;m interested to see a general solution, if there&#39;s any. Thanks.

JSLint message: Unused variables

JSLint site updated, and I cannot check JS scripts anymore. For me, this warning is not critical, and I don&#39;t want to go through thousands of lines to fix this, I want to find more critical problems.

Does anybody know how to turn off this error, or use legacy JSLint?

**UPDATE**

Example:

    function doSomethingWithNodes(nodes){
	  this.doSomething();

	  for (var i = 0; i &lt; nodes.length; ++i){
		this.doSomethingElse(nodes[i]);
	  }

	  doSomething(); // want to find this problem
	}

jslint.com output:

	Error:
	Problem at line 4 character 8: Move all &#39;var&#39; declarations to the top of the function.

	for (var i = 0; i &lt; nodes.length; ++i){

	Problem at line 4 character 8: Stopping, unable to continue. (44% scanned).

Problem:

Having variables on top of the functions is new requirement. I cannot use JSLINT to test code, because it stops scanning script on this error.

I have a lot of code, and do not want to threat this warning as critical error.

UPDATE 8/22/2011: found http://jshint.com, it looks much better than http://jslint.com/

JSLint error: Move all &#39;var&#39; declarations to the top of the function

I&#39;m using JSLint to verify most of my external Javascript files, but the largest amount of errors I&#39;m getting is from functions being used before they&#39;re defined.

**Is this really an issue I should worry about**?

It seems Firefox, IE7 and Chrome don&#39;t care. Functions like the popular `init()` (which I use often) normally stick at the top as that makes sense to me (I like to pretend it&#39;s analogous to `main()`) will, according to JSLint, need to be pushed to the bottom of the file.

JSLint: Using a function before it&#39;s defined error

So I&#39;m using [JSLint][1] to try and detect errors. I turn some options off I don&#39;t like, but I don&#39;t see any way to enable being able to use the `window` global variable. Well, there is the Yahoo Widget option, but that&#39;s overkill.

What&#39;s the deal with using &#39;window&#39;, why would JSLint say that is causing errors?

  [1]: http://en.wikipedia.org/wiki/JSLint


JSLint&#39;s issue with &#39;window&#39; as a global variable

What does **JSLint** mean by this error? And how should it be rewritten?

`Error: Problem at line 78 character 3: Move the invocation into the parens that contain the function: 
    })(jQuery);
`


JSLint error: &quot;Move the invocation into the parens that contain the function&quot;

What would be the correct way to solve the jslint error in this case? I&#39;m adding a getter function to an object which uses this. I don&#39;t know how to do this without creating the function inside the loop.

    for (var i = 0; i&lt;processorList.length; ++i) {
       result[i] = {
           processor_: timestampsToDateTime(processorList[i]),
           name_: processorList[i].processorName,
           getLabel: function() { // TODO solve function in loop.
                return this.name_;
           }
       };
    }


Don&#39;t make functions within a loop

JSLint is not passing this as a valid code:

    /* global someVar: false */
    if (typeof someVar === &quot;undefined&quot;) {
        var someVar = &quot;hi!&quot;;
    }

What is the correct way?

What is the correct way to check if a global variable exists?

I know that some people consider the presence of a leading underscore to imply that a variable is &quot;private,&quot; that such privacy is a fiction, and assume this is why JSLint reports such names with an error message.

I use Google Analytics on a Web site I am building. I make reference to GA&#39;s variables, such as &quot;_gaq.&quot;

I am trying to get my JS code to be 100% JSLint clean (I&#39;m not religious about my coding style, and so will go with Mr. Crockford&#39;s counsel). That said, I can&#39;t do anything about Google&#39;s variables names... so, I guess I can&#39;t get 100% &quot;clean.&quot;  

I post here in case I&#39;ve misunderstood the message, and can do something to comply with JSLint practices.

JSLint reports &quot;Unexpected dangling&quot; character in an underscore prefixed variable name

One of the [tips for `jslint` tool][1] is:

&gt; **`++` and `--`** 	 
&gt; The `++` (increment) and `--` (decrement) 
&gt; operators have been known to contribute to bad code by
&gt; encouraging excessive trickiness. They
&gt; are second only to faulty architecture
&gt; in enabling to viruses and other
&gt; security menaces. There is a plusplus
&gt; option that prohibits the use of these
&gt; operators.

I know that PHP constructs like `$foo[$bar++]` may easily result in off-by-one errors, but I couldn&#39;t figure out a better way to control the loop than a:
```
while( a &lt; 10 ) do { /* foo */ a++; }
```
or
```
for (var i=0; i&lt;10; i++) { /* foo */ }
```

Is the `jslint` highlighting them because there are some similar languages that lack the &quot;`++`&quot; and &quot;`--`&quot; syntax or handle it differently, or are there other rationales for avoiding &quot;`++`&quot; and &quot;`--`&quot; that I might be missing?

  [1]: http://www.jslint.com/lint.html


Why avoid increment (&quot;++&quot;) and decrement (&quot;--&quot;) operators in JavaScript?

JSLint is giving me this error:

&gt;Problem at line 11 character 33: Use the array literal notation [].

    var myArray = new Array();

What is array literal notation and why does it want me to use it instead?

It shows &lt;a herf=&quot;http://www.w3schools.com/JS/js_obj_array.asp&quot;&gt;here&lt;/a&gt; that `new Array();` should work fine... is there something I&#39;m missing?

What is array literal notation in javascript and when should you use it?

This is the error I get when using const:

    &lt;error line=&quot;2&quot; column=&quot;1&quot; severity=&quot;warning&quot; message=&quot;&amp;apos;const&amp;apos; is available in ES6 (use esnext option) or Mozilla JS extensions (use moz).&quot; source=&quot;jshint.W104&quot; /&gt;


My code looks like this:

    const Suites = {
        Spade: 1,
        Heart: 2,
        Diamond: 3,
        Club: 4
    };

The code works fine only JSHint is warning me every time.

Why does JSHint throw a warning if I am using const?

From time to time, I get TSLint errors &quot;block is empty&quot;. This happens e.g. when I pass a no-op callback to a function:

    doSomething(() =&gt; {});

From what I read, JSLint apparently does the same, but I didn&#39;t verify that.

I find these usages completely valid, so I tried to find a reason why empty blocks are considered bad at all. But the only thing I&#39;m able to find (e.g. in [this answer](https://stackoverflow.com/a/17685875/219187)) are instructions to add a `return;` to avoid the error. This is **not** what I want to do in every empty callback.

Why does TSLint report above empty block as problem? Is there any reason why I shouldn&#39;t disable the check?

Why do TSLint and JSLint report empty blocks?

JSLint (with the onevar flag turned on) is flagging some javascript code that I have with the following:

&lt;pre&gt;Problem at line 5 character 15: Too many var statements.&lt;/pre&gt;

I am happy to fix these errors, but I&#39;d like to know, am I doing it for performance or because it is just a bad practice and has a greater potential to introduce bugs in my javascript code.  What is the reason behind the onevar flag?

I did look at the JSLint docs for the [var keyword][1] but it doesn&#39;t specifically talk about why multiple var statements in the same function are bad.

Here is an attempt at an example.  Explain how the code will benefit from only having 1 var statement:

    function Test(arg) {
       var x = arg + 1,
           y = cache.GetItem(&#39;xyz&#39;);
       if (y !== null) {
          // This is what would cause the warning in JSLint
          var request = ajaxPost(/* Parameters here */);
          
       }
    }

  [1]: http://www.jslint.com/lint.html#var



What is the reason behind JSLint saying there are &quot;too many var statements&quot;

I am working on making all of our JS code pass through jslint, sometimes with a lot of tweaking with the options to get legacy code pass for now on with the intention to fix it properly later.

There is one thing that jslint complains about that I do not have a workround for. That is when using constructs like this, we get the error &#39;Don&#39;t make functions within a loop.&#39;

    for (prop in newObject) {
        // Check if we&#39;re overwriting an existing function
        if (typeof newObject[prop] === &quot;function&quot; &amp;&amp; typeof _super[prop] === &quot;function&quot; &amp;&amp;
            fnTest.test(newObject[prop])) {
            prototype[prop] = (function(name, func) {
                return function() {
                    var result, old_super;

                    old_super = this._super;
                    this._super = _super[name];
                    result = func.apply(this, arguments);
                    this._super = old_super;

                    return result;
                };
            })(prop, newObject[prop]);
        }
    }

This loop is part of a JS implementation of classical inheritance where classes that extend existing classes retain the super property of the extended class when invoking a member of the extended class.
Just to clarify, the implementation above is inspired by this [blog post][1] by John Resig.

But we also have other instances of functions created within a loop.

The only workaround so far is to exclude these JS files from jslint, but we would like to use jslint for code validation and syntax checking as part of our continuous integration and build workflow.

Is there a better way to implement functionality like this or is there a way to tweak code like this through jslint?


  [1]: http://ejohn.org/blog/simple-javascript-inheritance/

How to fix jslint error &#39;Don&#39;t make functions within a loop.&#39;?

I was just linting some JavaScript code using JSHint. In the code I have two for-loops both used like this: 

    for (var i = 0; i &lt; somevalue; i++) { ... }

So both for-loops use the var i for iteration.

Now JSHint shows me an error for the second for-loop: &quot;&#39;i&#39; is already defined&quot;. I can&#39;t say that this isn&#39;t true (because it obviously is) but I always thought this wouldn&#39;t matter as the var i is only used in that specific place. 

Is it bad practice to use for-loops this way? Should I use a different variable for each for-loop in my code like

    //for-loop 1
    for (var i = 0; ...; i++) { ... }
    
    //for-loop 2
    for (var j = 0; ...; j++) { ... }

Or is this on e of the errors I can ignore (because it doesn&#39;t break my code, it still does what it is supposed to do)?

JSLint btw. stops validating at the first for loop because I don&#39;t define var i at the top of the function (that&#39;s why I switched to JSHint in the first place). So according to the example in this question: https://stackoverflow.com/questions/6803305/should-i-use-jslint-or-jshint-javascript-validation/10763615#10763615 – I should use for-loops like this anyway to confirm JSLint: 

    ...
    var i;
    ...
    //for-loop 1
    for (i = 0; ...; i++) { ... }
    ...
    //for-loop 2
    for (i = 0; ...; i++) { ... }

This also looks good to me, because this way I should avoid both errors in JSLint and JSHint. But what I am uncertain about is if I should use a different variable for each for-loop like this: 

    ...
    var i, j;
    ...
    //for-loop 1
    for (i = 0; ...; i++) { ... }
    //for-loop 2
    for (j = 0; ...; j++) { ... }

So is there a best practice for this or could I just go with any of the codes above, meaning I choose &quot;my&quot; best practice?

Is it bad practice to use the same variable name in multiple for-loops?

I know this is silly, but there&#39;s any difference between this:

    (function() {  
        var foo = &#39;bar&#39;;  
    })();

and this?

    (function() {  
        var foo = &#39;bar&#39;;  
    }());

[JSLint][1] tells us to `Move the invocation into the parens that contain the function`, but I see no need to.

**Edit:** The answers are too cool. `~function`, the [JSHint][2] alternative along with jQuery&#39;s preference for `(/***/)();` and Crockford&#39;s explanation! I thought I was going to just get a &quot;they&#39;re the same thing&quot; kind of answer.  
You guys decide the best one through upvotes and I tick it.


  [1]: http://www.jslint.com/
  [2]: http://www.jshint.com/

(...()) vs. (...)() in javascript closures

I have been validating my JavaScript using JSLint for about 2 years now and once in a while there are rules that change. In general when JSLint introduces a new rule, there is a checkbox to ignore this rule when parsing, or if you choose to not ignore it then to make your code compliant to it.

As I was running my JSLint validation today, however, I run into these two new errors:

&gt; Use spaces, not tabs.

This is not the &quot;mixing of tabs and spaces&quot; error. I am using only tabs. This is a recently modified version of &quot;mixing of tabs and spaces&quot; which now disallows tabs in general.


And:

&gt; Unsafe character. 
&gt;
&gt; */
&gt; 
&gt; Unsafe character.     
&gt; 
&gt; _const: {


There are no new options to ignore. I cannot understand what is unsafe about closing a block comment, why it considers _const: { as unsafe when I have `nomen: true`, (dangling _ in identifiers) or why should I be suddenly switching from spaces to tabs, when I still have the configuration about indentation of 4 spaces being a tab. 

Does anyone have an idea why those were introduced to at least how to make JSLint ignore these new rules?

**Update:**
The *`Messy White Space`* option works around the issue but it would cause other unexpected behavior:

    if (condition) { 
      //            ^-- there is a space but it won&#39;t indicate an error

Why were the new JSLint errors &quot;use spaces, not tabs&quot; and &quot;unsafe character&quot; introduced?

JSLint complains that the following (useless example) code is invalid:

    (function (x) {
        &quot;use strict&quot;;
        if (x === 1) {
            return 1;
        } else if (x === 2) {
            return -1;
        }
        return 0;
    }(1));

&gt; Error:
&gt; Problem at line 4 character 9: Unexpected &#39;else&#39; after &#39;return&#39;.
&gt; 
&gt; return 1;

Is it seriously suggesting that it&#39;s bad to use return statements inside an if/else structure?

It thinks this version is fine:

    (function (x) {
        &quot;use strict&quot;;
        var returnval = 0;
        if (x === 1) {
            returnval = 1;
        } else if (x === 2) {
            returnval = -1;
        }
        return returnval;
    }(1));

Why does JSLint complain about &quot;Unexpected &#39;else&#39; after &#39;return&#39;&quot;?

Can anyone point to a functioning [JSLint][1] plug-in for Eclipse?

  [1]: http://www.jslint.com/

All Jslint Solutions on Gang of Coders

Total of 40 Jslint Solutions