Matchers

Overview

Matchers are functions that compare two values and return a boolean indicating whether they are considered equal or not.

Satisfies type FnMatch

areSame

Performs a strict equality comparison between two values using the === operator. This means that both the value and type must be the same.

Examples

areSame(1, 1) // => true
areSame(1, '1') // => false
areSame({}, {}) // => false

areSimilar

Performs a loose equality comparison between two values using the == operator. This means that the values are compared after type coercion.

Examples

areSimilar(1, 1) // => true
areSimilar(1, '1') // => true
areSimilar({}, {}) // => false

areSameValueZero

Performs a SameValueZero comparison between two values. This is similar to strict equality (===) but treats NaN as equal to itself and -0 as not equal to +0.

Examples

const object = { user: 'fred' }
const other = { user: 'fred' }

areSameValueZero(object, object) // => true
areSameValueZero(object, other) // => false
areSameValueZero('a', 'a') // => true
areSameValueZero('a', new Object('a')) // => false
areSameValueZero(Number.NaN, Number.NaN) // => true

areEqual

Performs a deep comparison between two values to determine if they are equivalent. This function supports comparing arrays, array buffers, booleans, date objects, error objects, maps, numbers, plain objects, regexes, sets, strings, symbols, and typed arrays. Functions and DOM nodes are not supported.

Examples

const object = { user: 'fred' }
const other = { user: 'fred' }

areEqual(object, other) // => true
object === other // => false

This utility is particularly useful when you need to check if two complex objects have the same structure and values.