Lodash _.over() Method

What You’ll Learn

By the end of this tutorial, you’ll use Lodash’s _.over() to run several functions on the same arguments and collect their results in one array.

What Is _.over()?

_.over(iteratees) builds a fan-out function. Call it once with any arguments; Lodash forwards those exact arguments to each iteratee and returns [result₁, result₂, …].

Use over when one input should produce several derived values—statistics, geometry metrics, or multiple property picks from the same object.

📝 Syntax

Pass an array of iteratees (functions or shorthands):

_.over([iteratees = [_.identity]])

Syntax Rules

• iteratees — array of functions; defaults to [_.identity].
• Return value — a new function that returns an array of iteratee results.
• Same arguments — every iteratee receives the full argument list from the outer call.
• Order preserved — result array matches iteratee order.
• Shorthands — property strings and other Lodash iteratee forms work in the list.

import over from "lodash/over";



const minMax = over([Math.min, Math.max]);



minMax(1, 2, 3, 4);

// [1, 4]

Examples Gallery

Practical _.over() patterns with copy-ready code, sample output, and interactive Try It Yourself labs.

const minMax = _.over([Math.max, Math.min]);



console.log(minMax(1, 2, 3, 4));

// [4, 1]

[4, 1]

const square = (n) => n * n;

const cube = (n) => n * n * n;



const powers = _.over([square, cube]);



console.log(powers(3));

// [9, 27]

[9, 27]

const area = (length, width) => length * width;

const perimeter = (length, width) => 2 * (length + width);



const rectangleMetrics = _.over([area, perimeter]);



console.log(rectangleMetrics(4, 6));

// [24, 20]

[24, 20]

const user = { name: "Ada", age: 30, role: "admin" };



const pickFields = _.over(["name", "age"]);



console.log(pickFields(user));

// ["Ada", 30]

["Ada", 30]

const pickFirstAndSecond = _.over([_.nthArg(0), _.nthArg(1)]);



console.log(pickFirstAndSecond("apple", "banana", "cherry"));

// ["apple", "banana"]

["apple", "banana"]

const inc = (n) => n + 1;

const dbl = (n) => n * 2;



console.log(_.over([inc, dbl])(3));

// [4, 6] — both get 3



console.log(_.flow([inc, dbl])(3));

// 8 — inc(3)=4, then dbl(4)=8

[4, 6]

8

📝 Notes

• _.over is parallel fan-out—not sequential like _.flow().
• Result order matches iteratee order—document which index means what.
• Default iteratees [_.identity] wrap a single value: _.over()(x) → [x].
• If any iteratee throws, the entire combinator throws—wrap risky iteratees if needed.
• For “all predicates true” use overEvery; for “any true” use overSome.
• Next in the series: _.overEvery()—boolean all-check combinator.

💡 Best Practices