Benchmark: Checking for presence of object key - MeasureThat.net

Script Preparation code:

var obj = {
   'first' : 1,
   'is' : 1,
   'some' : 1,
   'nice' : 1,
   'test' : 1,
   'last' : 1
}

Tests:

in – first element
if ('first' in obj) { }
in – last element
if ('last' in obj) { }
typeof – first element
if (typeof obj['first'] !== "undefined") { }
typeof – last element
if (typeof obj['last'] !== "undefined") { }
! – first element
if (!obj['first']) { }
! – last element
if (!obj['last']) { }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
in – first element
in – last element
typeof – first element
typeof – last element
! – first element
! – last element

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:108.0) Gecko/20100101 Firefox/108.0

Browser/OS: Firefox 108 on Ubuntu

View result in a separate tab

Test name	Executions per second
in – first element	811561700.0 Ops/sec
in – last element	842012200.0 Ops/sec
typeof – first element	858163800.0 Ops/sec
typeof – last element	840668400.0 Ops/sec
! – first element	865953200.0 Ops/sec
! – last element	861358700.0 Ops/sec