Info

at what point is it cheaper to inherit properties than copy them for arrays

Preparation code

<script>
var small_array = [1,2,3,4,5];
var medium_array = []
var large_array = []
for (var i=0;i<100;i++)medium_array.push(i);
for (var i=0;i<1000;i++)large_array.push(i);
function copy(array){
  var i = array.length
  var res = {length:i}
  while(i--) res[i] = array[i];
  return res
}
</script>

Test runner

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Object.create(medium_array);

copy(small_array);

copy(medium_array);

copy(large_array);

medium_array.slice();

small_array.slice();

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