Building string via loop vs. join

JavaScript performance comparison

Test case created

Preparation code

 
<script>
  Benchmark.prototype.setup = function() {
    var result = "";
    var array = ["alpha", "beta", "gamma", "delta", "epsilon", "pi", "mu", "nu", "omicron", "lambda"];
  };
</script>

Test runner

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Testing in unknown unknown
Test Ops/sec
Loop
 
for (var i = 0; i < array.length; i++) {
   results += (results == "" ? "" : ",") + array[i];
}
 pending…
Join
 
var outputArray = [];
outputArray.push(array[0]);
outputArray.push(array[1]);
outputArray.push(array[2]);
outputArray.push(array[3]);
outputArray.push(array[4]);
outputArray.push(array[5]);
outputArray.push(array[6]);
outputArray.push(array[7]);
outputArray.push(array[8]);
outputArray.push(array[9]);
var results = outputArray.join(",")
 
 pending…
Loop 2
 
for (var i in array) {
   results += (results == "" ? "" : ",") + array[i];
}
 pending…
Join 2
 
var outputArray = [];
outputArray[outputArray.length] = array[0];
outputArray[outputArray.length] = array[1];
outputArray[outputArray.length] = array[2];
outputArray[outputArray.length] = array[3];
outputArray[outputArray.length] = array[4];
outputArray[outputArray.length] = array[5];
outputArray[outputArray.length] = array[6];
outputArray[outputArray.length] = array[7];
outputArray[outputArray.length] = array[8];
outputArray[outputArray.length] = array[9];
var results = outputArray.join(",")
 
 pending…
Loop 3
 
var i = 0;
while (i < array.length) {
   results += (results == "" ? "" : ",") + array[i++];
}
 pending…

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