deep-key

deep-key is a utility for working with deeply nested objects in TypeScript. It helps you read, filter, sort, and update properties without writing manual guards at every level.

Features

• Safe access to nested properties.
• Reading and mapping arrays with dynamic paths.
• Filtering arrays by nested properties.
• Sorting arrays by nested properties.
• Immutable updates for nested values.

Documentation

• Value utilities
• Filter utilities
• Sort utilities
• Exported types

Installation

npm install @nuc-lib/deep-key

Usage

import {
    filterByKeyValue,
    getKeyValue,
    sortByKeyValue,
    updateKeyValue
} from '@nuc-lib/deep-key';

If you want to see every scenario covered by each utility, check the separate documentation files in docs/.

Reading and updating values

See docs/value.md for getKeyValue and updateKeyValue examples.

Filtering and sorting

See docs/filter.md for filterByKeyValue and docs/sort.md for sortByKeyValue.

Quick examples

const guy = {
    personalInfo: { name: 'John Doe' },
    contacts: [{ name: 'Jane Doe' }, { name: 'Alice Smith' }]
};

getKeyValue({ object: guy, key: 'personalInfo.name' });
// 'John Doe'

getKeyValue({ object: guy, key: '[contacts].name' });
// ['Jane Doe', 'Alice Smith']

updateKeyValue({
    object: guy,
    key: 'personalInfo.name',
    value: 'Jane Smith'
});
// { personalInfo: { name: 'Jane Smith' }, contacts: [{ name: 'Jane Doe' }, { name: 'Alice Smith' }] }

filterByKeyValue({
    array: [{ age: 25 }, { age: 30 }],
    key: 'age',
    filter: (value) => value === 30
});
// [{ age: 30 }]

sortByKeyValue({
    array: [{ name: 'Bob' }, { name: 'Alice' }],
    key: 'name'
});
// [{ name: 'Alice' }, { name: 'Bob' }]