Run results for: Testing var undefined comparison & checking it via object/array. - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.57.2 (KHTML, like Gecko) Version/5.1.7 Safari/534.57.2

Browser: Safari 5

Operating system: Windows 7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
!var1	14458291.0 Ops/sec
var1===undefined	6439725.0 Ops/sec
var1 \|\| var1==="" \|\| var1===0	5894138.0 Ops/sec
!(1 in arguments)	3296170.5 Ops/sec
!arguments[1]	3139334.0 Ops/sec
!object["var"]	7739540.5 Ops/sec
!object[0]	7278978.5 Ops/sec
!arguments["string"]	3440598.0 Ops/sec

Script Preparation code:

var var1;
var arguments = ["sdfe"];
arguments["string"] = "data";
var object = {option:"yes", 0:"ok"};

Tests:

!var1
if(!var1);
var1===undefined
if(var1===undefined);
var1 || var1==="" || var1===0
if(var1 || var1==="" || var1===0);
!(1 in arguments)
if(!(1 in arguments));
!arguments[1]
if(!arguments[1]);
!object["var"]
if(!object["var"]);
!object[0]
if(!object[0]);
!arguments["string"]
if(!arguments["string"]);

;