Run results for: combined map-join vs native map + join v2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser: Chrome 114

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 11 months ago

Script Preparation code:

var data = Array(1000000).fill({ a: 'a', b: 1 });

Tests:

mapJoin +
function mapJoin(data, func, joinStr) { data.reduce((prev, item)=> { return prev + joinStr + func(item) }, '') } mapJoin(data, x => `${x.a}_${x.b}`, ',')
native map + join
data.map(x => `${x.a}_${x.b}`).join(',')
mapJoin - string literal
function mapJoin(data, func, joinStr) { data.reduce((prev, item)=> { return `${prev}${joinStr}${func(item)}` }, '') } mapJoin(data, x => `${x.a}_${x.b}`, ',')
mapJoin - concat
function mapJoin(data, func, joinStr) { data.reduce((prev, item)=> { return prev.concat(joinStr, func(item)) }, '') } mapJoin(data, x => `${x.a}_${x.b}`, ',')