is-subset

What is is-subset?

The is-subset npm package is a utility that allows you to check if one set of values is a subset of another. This can be particularly useful for validating data structures, filtering data, and performing set operations in JavaScript.

What are is-subset's main functionalities?

Basic Subset Check

This feature allows you to check if one object is a subset of another. In this example, object `b` is a subset of object `a` because all key-value pairs in `b` exist in `a`.

const isSubset = require('is-subset');
const a = { foo: 'bar', baz: 42 };
const b = { foo: 'bar' };
console.log(isSubset(a, b)); // true

Array Subset Check

This feature allows you to check if one array is a subset of another. In this example, array `b` is a subset of array `a` because all elements in `b` exist in `a`.

const isSubset = require('is-subset');
const a = [1, 2, 3, 4];
const b = [2, 3];
console.log(isSubset(a, b)); // true

Nested Object Subset Check

This feature allows you to check if one nested object is a subset of another. In this example, object `b` is a subset of object `a` because the nested structure and values in `b` exist in `a`.

const isSubset = require('is-subset');
const a = { foo: { bar: 'baz' }, qux: 42 };
const b = { foo: { bar: 'baz' } };
console.log(isSubset(a, b)); // true

Other packages similar to is-subset

lodash.isequal

Lodash's `isEqual` function can be used to perform deep comparisons between two values to determine if they are equivalent. While it is more general-purpose and can compare any two values for equality, it does not specifically check for subset relationships.

underscore

Underscore.js provides a variety of utility functions for JavaScript, including `_.isMatch`, which can be used to check if an object contains certain key-value pairs. This is similar to checking for subsets but is more focused on object properties.

deep-equal

The `deep-equal` package allows for deep comparison between two values to determine if they are equivalent. Like `lodash.isequal`, it is more general-purpose and does not specifically check for subset relationships.

README

     

is-subset

Check if an object is contained within another one.

Installation

$ npm install is-subset

Usage

1. Import the module:

import isSubset from 'is-subset/module';

// …or:
var isSubset = require('is-subset');

1. These are true:

isSubset(
  {a: 1, b: 2},
  {a: 1}
);

isSubset(
  {a: 1, b: {c: 3, d: 4}, e: 5},
  {a: 1, b: {c: 3}}
);

isSubset(
  {a: 1, bcd: [1, 2, 3]},
  {a: 1, bcd: [1, 2]}
);

…and these are false:

isSubset(
  {a: 1},
  {a: 2}
);

isSubset(
  {a: 1},
  {a: 1, b: 2}
);

isSubset(
  {a: 1, bcd: [1, 2, 3]},
  {a: 1, bcd: [1, 3]}
);

See the specs for more info.

API

isSubset(superset, subset)

Check if an object is contained within another object.

Returns true if:

• all enumerable keys of subset are also enumerable in superset, and
• every value assigned to an enumerable key of subset strictly equals the value assigned to the same key of superset – or is a subset of it.

Parameters:

• Object superset
• Object subset

Return value:

• Boolean

License

MIT © Studio B12 GmbH