Info

Fastest way to check if variable is siring

Preparation code

 
<script>
  Benchmark.prototype.setup = function() {
    if (!"dsfsad".isString) {
        String.prototype.isString = true;
    
        $ = {};
    
        $.defineMethod = function(obj, method, fn) {
                Object.defineProperty(obj, method, {
                        value: fn,
                        enumerable: false
                });
        };
    
        $.defineMethod(window, 'isString', function (value){
                return typeof value == 'string' || value instanceof String;
        });
    
        $.defineMethod(window, 'isString2', function (value){
                return value.isString? true: false;
        });
    
    window.isString3 = function(value){return typeof value == 'string' || value instanceof String;}
    }
    
    var a = "DFADSF";
    var b = {c:10};
  };
</script>

Test runner

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Java applet disabled.

isString(a);

 

isString2(a);

isString(b);

isString2(b);

isString3(a);

isString3(b);

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by Mikhail Shestakov on 1st March 2013
• Revision 2: published on 1st March 2013
• Revision 3: published on 1st March 2013
• Revision 4: published by Mikhail Shestakov on 1st March 2013

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