Run details:
Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36 OPR/41.0.2353.69
Opera 41
Windows
Other
7 years ago
Test name Executions per second
typeof x === "undefined" 7041780.5 Ops/sec
x === undefined 2772219.0 Ops/sec
x == undefined 2781072.5 Ops/sec
x == null 7507955.5 Ops/sec
Script Preparation code:
Tests:
  • typeof x === "undefined"

  • x === undefined

  • x == undefined

  • x == null


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