JSLint is suddenly reporting: Use the function form of "use strict"

javascript jslint
Zhami picture Zhami · Dec 16, 2010 · Viewed 282.2k times · Source

I include the statement:

"use strict";

at the beginning of most of my Javascript files.

JSLint has never before warned about this. But now it is, saying:

Use the function form of "use strict".

Does anyone know what the "function form" would be?

Answer

bdukes picture bdukes · Dec 16, 2010

Include 'use strict'; as the first statement in a wrapping function, so it only affects that function. This prevents problems when concatenating scripts that aren't strict.

See Douglas Crockford's latest blog post Strict Mode Is Coming To Town.

Example from that post:

(function () {
   'use strict';
   // this function is strict...
}());

(function () {
   // but this function is sloppy...
}());

Update: In case you don't want to wrap in immediate function (e.g. it is a node module), then you can disable the warning.

For JSLint (per Zhami):

/*jslint node: true */

For JSHint:

/*jshint strict:false */

or (per Laith Shadeed)

/* jshint -W097 */

To disable any arbitrary warning from JSHint, check the map in JSHint source code (details in docs).

Update 2: JSHint supports node:boolean option. See .jshintrc at github.

/* jshint node: true */

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