flattie

library1.1.1jsnpmunverified

Flattie is a minimalist and highly performant JavaScript utility for recursively flattening nested objects and arrays into a single-depth object. Currently at version 1.1.1, the library maintains a stable release cadence with incremental patches. Its core differentiators include its extremely small bundle size (203B), demonstrated speed via benchmarks against alternatives like `flat` and `flatten-object`, and customizable behavior for key concatenation via a 'glue' string. By default, it automatically omits nullish values (`null`, `undefined`) from the flattened output, a feature that can be toggled. It also ships with TypeScript type definitions, providing a robust developer experience. Its counterpart, `nestie`, provides the reverse operation (expanding flattened objects).

serialization data

npm install flattie

github ↗package ↗

INSTALL

IMPORT

SIG · FLATTIE

flattie

serializationjavascriptv1.1.1

Install

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Import

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Disk

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Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

flattie

✓ import { flattie } from 'flattie';

✗ import flattie from 'flattie'; const flattie = require('flattie');

The primary flattening function is a named export. It is not a default export, and CommonJS `require` should use destructuring.

Demonstrates basic object flattening, custom glue usage, and how to retain nullish values.

import { flattie } from 'flattie'; const nestedObject = { user: 'alice', profile: { email: 'alice@example.com', settings: { theme: 'dark', notifications: true, preferences: [ { id: 1, value: 'optionA' }, { id: 2, value: null }, { id: 3, value: 'optionC' } ] } }, status: null, tags: ['admin', 'premium'] }; // Flatten the object with default glue ('.') and nullish purging (true) const flatDefault = flattie(nestedObject); console.log('Default Flattened:', flatDefault); // Flatten the object keeping nullish values const flatKeepNullish = flattie(nestedObject, '.', true); console.log('Flattened (keeping nullish):', flatKeepNullish); // Flatten the object with a custom glue const flatCustomGlue = flattie(nestedObject, '__'); console.log('Flattened (custom glue):', flatCustomGlue);

Debug

Known issues

gotchaBy default, `null` and `undefined` values are automatically excluded from the flattened output. This behavior might be unexpected if you intend to preserve all original data points.

fix

To retain nullish values, pass `true` as the third argument to the `flattie` function: `flattie(input, glue, true)`.

affects: >=1.0.0

gotchaFlattie always returns a new object, even if the input is an array. Array elements will be mapped to keys using their numerical indices combined with the specified glue string.

fix

Be aware that the output format is consistently an object. If an array is desired, a post-processing step to convert the flattened object back into an array structure would be necessary.

affects: >=1.0.0

gotchaWhile `null` and `undefined` are purged, other 'empty' or special values like empty strings (`''`) or `NaN` are preserved in the output by default.

fix

If specific handling for empty strings, `NaN`, or other non-nullish but undesirable values is required, implement custom pre-processing on the input or post-processing on the flattened output.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: flattie is not a function

Attempting to import `flattie` as a default export or using `require()` without destructuring in a CommonJS environment. The `flattie` function is a named export.

fix

For ESM, use `import { flattie } from 'flattie';`. For CommonJS, use `const { flattie } = require('flattie');`.

Object.prototype.hasOwnProperty.call is not a function

This error typically indicates an issue with an object not being a plain object or potential environment incompatibility, though less common with `flattie`'s focused scope. It might occur if `input` is a primitive or a highly custom object lacking standard `Object.prototype` methods.

fix

Ensure the `input` provided to `flattie` is a valid JavaScript object or array. Verify your Node.js version is `>=8` as specified in the package engines.

Upgrade

Version history

1.1.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

8 hits · last 30 days

node

Resources

githubhttps://github.com/lukeed/flattie ↗

packagehttps://www.npmjs.com/package/flattie ↗