Array.length outside a loop

JavaScript performance comparison

Test case created

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var myArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100],
        arrayLength = myArray.length,
          index,
        sum;
};

Benchmark.prototype.teardown = function() {
     
   
};
</script>

Test runner

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Testing in unknown unknown
Test Ops/sec
bad-loop
for ( index = 0; index < myArray.length; index++ ) {
        sum += myArray[index];
}
pending…
good-loop
for ( index = 0; index < arrayLength; index++ ) {
        sum += myArray[index];
}
pending…

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