Double Lookup

JavaScript performance comparison

Revision 3 of this test case created

Info

Testing the equivalent of map.hasKey vs map.get for finding out if an object has a particular member.

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var x = {a: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, b: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, c: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, d: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, e: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, f: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, g: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, h: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, i: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, j: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, k: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, l: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, m: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, n: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, o: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, p: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, q: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, r: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, s: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, t: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}, u: {a: 0, b: 1, c: 2, d: 3, e: 4, f: 5, g: 6, h: 7, i: 8, j: 9, k: 10, l: 11, m: 12, n: 13, o: 14, p: 15, q: 16, r: 17, s: 18, t: 19, u: 20}};
    var y = [
      "a", "_b", "c", "_d", "e", "_f", "g", "_h", "i", "_j", "k", "_l", "m",
      "n", "_o", "p", "_q", "r", "_s", "t", "_u", "v", "_w", "x", "_y", "z"];
   
    x.zz = 0;
    delete x.zz;
   
   
};
</script>

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Testing in unknown unknown
Test Ops/sec
Double-Get
for (var i = 0; i < y.length; ++i) {
  var v = null;
  var k = y[i];
  if (x[k] !== undefined) {
     v = x[k];
  }
}
   
pending…
Key Check (Own)
for (var i = 0; i < y.length; ++i) {
  var v = null;
  var k = y[i];
  if (x.hasOwnProperty(k)) {
     v = x[k];
  }
}
   
pending…
Key Check (General)
for (var i = 0; i < y.length; ++i) {
  var v = null;
  var k = y[i];
  if (k in x) {
     v = x[k];
  }
}
   
pending…

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