Benchmark: flatMap vs reduce vs loop filtering performance vs flat.map

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); }
map flat()
arr.flat().map((o) => o.assigned ? [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
map flat()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36

Browser/OS: Chrome 142 on Linux

View result in a separate tab

loop with push

34K/s

reduce with push

20K/s

flatMap

6K/s

map flat()

6K/s

View exact numbers

Test name	Executions per second
✓ loop with push	33,513 Ops/sec
reduce with push	20,423 Ops/sec
flatMap	5,683 Ops/sec
map flat()	5,564 Ops/sec

flatMap vs reduce vs loop filtering performance vs flat.map (version: 1)

https://stackoverflow.com/a/77247681

Comparing performance of: `flatMap vs reduce with push vs loop with push vs map flat()`

Created: 8 months ago by: Guest

Go to the latest result

flatMap

reduce with push

loop with push

map flat()

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

flatMap vs reduce vs loop filtering performance vs flat.map (version: 1)

https://stackoverflow.com/a/77247681

Comparing performance of: flatMap vs reduce with push vs loop with push vs map flat()

Created: 8 months ago by: Guest

Go to the latest result

flatMap

reduce with push

loop with push

map flat()

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 map flat()`