Checking for null or undefined

JavaScript performance comparison

Test case created by watson

Preparation code


      
      <script>
Benchmark.prototype.setup = function() {
  let x = null
  let n = 0

};
</script>

Test runner

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Java applet disabled.

Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Casting
if (!x) {
  // allow if-block to run a few times
  x = ++n > 10 ? true : null
}
pending…
No casting (undefined first)
if (x === undefined || x === null) {
  // allow if-block to run a few times
  x = ++n > 10 ? true : null
}
pending…
No casting (null first)
if (x === null || x === undefined) {
  // allow if-block to run a few times
  x = ++n > 10 ? true : null
}
pending…
Weak equals
if (x == null) {
  // allow if-block to run a few times
  x = ++n > 10 ? true : null
}
pending…

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