Test Undefined Check

JavaScript performance comparison

Test case created by Josh

Info

Testing performance of different undefined checks

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var undefined, definedFalsy = "", defined = { test: "value" };
   
    function checkWithFalsy(obj) {
      return obj && typeof obj !== "undefined";
    }
   
    function checkWithoutFalsy(obj) {
      return typeof obj !== "undefined";
    }
};
</script>

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Testing in unknown unknown
Test Ops/sec
Falsey
checkWithFalsy(function() {});
 
pending…
Regular
checkWithoutFalsy(function() {});
pending…

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