Native map vs. forEach appending vs. array looping (v8)

Revision 8 of this benchmark created by Ruquay Calloway on

Preparation HTML

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.4.4/underscore-min.js">
</script>
<script>
  var g = [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];
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
Map (native)
var h = g.map(function(x) {
 return x + 2
});
ready
forEach (native)
var h = [];
g.forEach(function(x) {
 h.push(x + 2);
})
ready
Loop
var h = [];
for (var i = 0, len = g.length; i < len; i++) {
 h.push(g[i] + 2);
}
ready
jquery each
var h = [];
$.each(g, function(i, gi){
 h.push(gi + 2);
});
ready
underscore each
var h = [];
_.each(g, function(i, gi){
 h.push(gi + 2);
});
ready
for in
var h = [];
for (var i in g) {
 h.push(g[i] + 2);
}
ready
loop 2
var h = [];
for (var i = 0; i < g.length; i++) {
 h.push(g[i] + 2);
}
ready
loop 3 (decrement)
var h = [];
for (var i = g.length - 1; i > -1; i--) {
 h[i] = g[i] + 2;
}
ready

Revisions

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