Disallow Unnecessary Strict Pragma (no-extra-strict)

Deprecation notice: This rule is deprecated and has been superseded by the strict rule. It will be removed in ESLint v1.0. Both "global" and "function" mode in the strict rule implement this rule’s behavior.

The "use strict"; directive applies to the scope in which it appears and all inner scopes contained within that scope. Therefore, using the "use strict"; directive in one of these inner scopes is unnecessary.

"use strict";

(function () {
    "use strict";
    var foo = true;
}());

Rule Details

This rule is aimed at preventing unnecessary "use strict"; directives. As such, it will warn when it encounters a "use strict"; directive when already in strict mode.

The following patterns are considered warnings:

"use strict";

(function () {
    "use strict";
    var foo = true;
}());

The following patterns are not considered warnings:

"use strict";

(function () {
    var foo = true;
}());

(function () {
    "use strict";
    var foo = true;
}());

Further Reading

• The ECMAScript 5 Annotated Specification - Strict Mode

Version

This rule was introduced in ESLint 0.3.0.

Resources

• Rule source
• Documentation source