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Is it better to spend time up front constructing arrays of objects without holes? Or to just check for holes when you iterate?

Preparation code

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
 
<script>
  Benchmark.prototype.setup = function() {
    var simple = [], complex = [],
      selectIndexes = [1, 2, 10, 14, 300, 1000],
      pairs = [
        { "id" : 1,
          "name" : "Albert"
        },
        { "id" : 2,
          "name" : "Bailey"
        },
        { "id" : 4,
          "name" : "Charlotte"
        },
        { "id" : 5,
          "name" : "Darlene"
        },
        { "id" : 10,
          "name" : "Edna"
        },
        { "id" : 12,
          "name" : "Faron"
        },
        { "id" : 13,
          "name" : "Gary"
        },
        { "id" : 14,
          "name" : "Helen"
        },
        { "id" : 15,
          "name" : "Igor"
        },
        { "id" : 16,
          "name" : "Justin"
        },
        { "id" : 17,
          "name" : "Kyle"
        },
        { "id" : 300,
          "name" : "Lynette"
        },
        { "id" : 500,
          "name" : "Morgan"
        },
        { "id" : 1000,
          "name" : "Nora"
        }
      ],
    
      get = function (a, i) {
        var ret = null;
        $.each(a, function () {
          if (this.id === i.valueOf()) {
            ret = this;
          }
        });
        return ret;
      };
  };

  Benchmark.prototype.teardown = function() {
    simple = [], complex = [];
  };
</script>

Preparation code output

Test runner

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$.each(pairs, function () {
  simple[this.id] = this.name;
});

$.each(simple, function () {
  if (this && this !== window) {
    this.charAt(0);
  }
});

$.each(selectIndexes, function () {
  simple[this].charAt(0);
});

$.each(pairs, function () {
  complex.push(this);
});

$.each(complex, function () {
  this.name.charAt(0);
});

$.each(selectIndexes, function () {
  get(complex, this).name.charAt(0);
});

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