dot-path-value

Safely get deep nested properties using dot notation.

Features

• TypeScript first 🤙
• Support arrays
• Tiny
• No dependencies
• Utility types Path and PathValue

Installation

# using npm
npm install dot-path-value
# using pnpm
pnpm install dot-path-value
# using yarn
yarn add dot-path-value

Usage

import { getByPath } from 'dot-path-value';

const obj = {
  a: {
    b: 'hello',
    d: [
      {
        e: 'world',
      }
    ],
  },
};

// access through object
getByPath(obj, 'a.b'); // outputs 'hello' with type `string`

// access through array
getByPath(obj, 'a.d.0.e'); // outputs 'world' with type `string`
getByPath(obj, 'a.d.0'); // outputs '{ e: 'world' }' with type `{ e: string }`

// also you can pass array as first argument
getByPath([{ a: 1 }], '0.a'); // outputs '1' with type `number`

// typescript errors
getByPath(obj, 'a.b.c'); // `c` property does not exist

Types

dot-path-value exports a few types to ensure the type safety:

Type	Description
Path<T>	converts nested structure T into a string representation of the paths to its properties
PathValue<T, TPath>	returns the type of the value at the specified path

Types usage

import { Path, PathValue } from 'dot-path-value';

const obj = {
  a: {
    b: 'hello',
    d: [
      {
        e: 'world',
      }
    ],
  },
};

type Foo = Path<typeof obj>; // 'a.d' | 'a' | 'a.b' | `a.d.${number}` | `a.d.${number}.e`
type Bar = PathValue<typeof obj, 'a.b'>; // 'string'