I'm trying to make my code JavaScript "strict", so I'm running it through JSLint to ensure my code is compliant.

However, on the following code:

setTimeout("getExtJs()", 2000);

I receive the following error:

Implied eval is evil. Pass a function instead of a string.

How do I make my code JavaScript "strict"?

I'm trying to make my code JavaScript "strict", so I'm running it through JSLint to ensure my code is compliant.

However, on the following code:

setTimeout("getExtJs()", 2000);

I receive the following error:

Implied eval is evil. Pass a function instead of a string.

How do I make my code JavaScript "strict"?

• javascript
• jslint

• See Implied eval is evil. – showdev Commented Apr 13, 2019 at 11:22

5 Answers 5

setTimeout(getExtJs, 2000);

Note that there are no quotes around getExtJs, I am passing the function not a String.

EDIT: As noted in the comments the reason why JSLint is upset is that when the first argument is a String it is processed as code to be executed in the same manner as eval()

See https://developer.mozilla.org/en/window.setTimeout

To find out why eval() (and by extension using Strings as the 1st argument here) is evil see the Mozilla Developer Network entry for eval.

It shouldn't complain if you do:

setTimeout(function(){
  // your code of this function getExtJs here
}, 2000);

Or:

setTimeout(getExtJs, 2000);

Although I don't see anything wrong in your implementation security-wise or otherwise.

Like it says, pass in the function (no quotes around the function name):

setTimeout(getExtJs, 2000);

When you pass in a string ("getExtJs"), setTimeout end up evaling it. Instead of that, it is better to simply pass in the function itself (getExtJs).

setTimeout(function () {getExtJs();}, 2000);

The correct syntax is

setTimeout(getExtJs, 2000);

You pass a reference to the function, and after 2000ms the function is executed. If you put parens after the function name, you are executing the function instead of referencing it.