Object keys iteration

JavaScript performance comparison

Revision 21 of this test case created by Alex Shvets

Info

Testing Object.keys vs for-in. I see that SlickGrid uses objects with indexed keys rather than arrays. Confused....

Preparation code

<script>
  var data = {};
 
  for (var i = 0; i < 10000; i++) {
 
   data[i] =  'user ' + i;
 
  }
</script>

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Testing in unknown unknown
Test Ops/sec
for-in
for (var key in data) {
   if (data.hasOwnProperty(key)) {
      data[key];
   }
}
pending…
object-keys
Object.keys(data).forEach(function(element, index, array){
  data[element];
});
pending…
object-keys 2
var keys = Object.keys(data);
var len = keys.length;
var i = 0;

while (i < len) {
   data[keys[i]];
   i++;
}
pending…
object-keys 3
var keys = Object.keys(data);
var len = keys.length;
var i;

for (i = 0; i < len; ++i) {
  data[keys[i]];
}
pending…
object-keys pop
var keys = Object.keys(data), i;
while (i = keys.pop() ) {
  data[keys[i]];
}
pending…

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