obj-path-attic

obj-path-attic is a work-in-progress utility for handling deeply nested object paths in JavaScript and TypeScript. It currently supports setting values on objects using a combination of dot and bracket notation. This library aims to provide a flexible and type-safe alternative to existing packages like object-path.

⚠️ This library is not production-ready yet. Use at your own risk.

Features

• Set nested properties: Add or update deeply nested properties in objects with dot and bracket notation.

• Flexible handling of object and array paths: Supports mixed dot and bracket notation for accessing arrays and objects.

Installation

npm install obj-path-attic

yarn add obj-path-attic

pnpm add obj-path-attic

Current API

setOnPath

setOnPath(obj: Obj, path: string, value: unknown): void

Sets a value in a nested object, creating intermediate objects or arrays as needed.

import { setOnPath } from "obj-path-attic";

const obj = {};
setOnPath(obj, "nested[0].key", "value");
console.log(obj);
// Output: { nested: [{ key: "value" }] }

Known Issues

1. Setting values via array notation on objects

If a property is accessed with array notation ([]) but already exists as an object, the value will be added as a key instead of modifying the array.

Example:

const obj = { nested: { foo: "bar" } };
setOnPath(obj, "nested[1]", "test");
console.log(obj);
// Output: { nested: { foo: "bar", 1: "test" } }

2. Setting values via object notation on arrays

Conversely, attempting to set an object property on an existing array will throw an error.

Solutions in the future

TypeScript template literal types may be used to address these issues in the future.

Planned Features

• Get: Retrieve values from objects using the same flexible path notation.
• Delete: Remove properties from nested objects or arrays.
• Empty: Clear specific nested paths.

Comparison with object-path

Unlike object-path, this library:

• Supports mixed dot and bracket notation.
• Allows explicit handling of numeric keys for objects or arrays.

Example:

import { setOnPath } from "obj-path-attic";

const obj = {};
setOnPath(obj, "foo.42[0]", "bar");
console.log(obj);
// Output: { foo: { 42: ["bar"] } }

object-path would treat 42 as an array index as it only uses the dot notation. This way numerical keys for arrays are not supported.

License

MIT © @jan-eckerlein