JavaScript doesn't care if your Strings are double-quoted "double"
or single-quoted 'single'
.
Every example of ECMAScript 5's strict mode has it enabled by "use strict"
in double-quotes. Can I do the following (single-quotes):
alert(function(){
'use strict';
return !this;
}());
This will return true if Strict mode is enabled, and false if it is not.
For you, without using a browser that supports strict mode :
A Use Strict Directive is an
ExpressionStatement
in a Directive Prologue whoseStringLiteral
is either the exact character sequences"use strict"
or'use strict'
. A Use Strict Directive may not contain an EscapeSequence or LineContinuation.
http://ecma262-5.com/ELS5_HTML.htm#Section_14.1
A Use Strict Directive is an ExpressionStatement in a Directive Prologue whose StringLiteral is either the exact character sequences "use strict" or 'use strict' . A Use Strict Directive may not contain an EscapeSequence or LineContinuation.
According to the mozilla documentation you can use both "use strict";
and 'use strict';
.
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