Benchmark: flatMap vs reduce vs loop filtering performance vs filter

Script Preparation code:

var arr = Array.from({length:10000}, (v, i) => ({name: i, assigned: Math.random() < 0.5}));

Tests:

flatMap
arr.flatMap((o) => (o.assigned ? [o.name] : []));
reduce with push
arr.reduce((a, o) => (o.assigned && a.push(o.name), a), [])
loop with push
{ const a = []; for (const o of arr) if (o.assigned) a.push(o.name); }
Filtermap
arr.filter(o => o.assigned).map(o => o.name)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
flatMap
reduce with push
loop with push
Filtermap

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

loop with push

30K/s

reduce with push

23K/s

Filtermap

20K/s

flatMap

2K/s

View exact numbers

Test name	Executions per second
✓ loop with push	30,288 Ops/sec
reduce with push	22,659 Ops/sec
Filtermap	20,122 Ops/sec
flatMap	2,404 Ops/sec

flatMap vs reduce vs loop filtering performance vs filter (version: 0)

https://stackoverflow.com/a/77247681

Comparing performance of: `flatMap vs reduce with push vs loop with push vs Filtermap`

Created: 2 years ago by: Guest

Go to the latest result

flatMap

reduce with push

loop with push

Filtermap

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

flatMap vs reduce vs loop filtering performance vs filter (version: 0)

https://stackoverflow.com/a/77247681

Comparing performance of: flatMap vs reduce with push vs loop with push vs Filtermap

Created: 2 years ago by: Guest

Go to the latest result

flatMap

reduce with push

loop with push

Filtermap

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `flatMap vs reduce with push vs loop with push vs Filtermap`