effect-io-ai

Package: effect
Module: Option

Option.makeEquivalence

Creates an Equivalence for Option<A> from an Equivalence for A.

When to use

Use when you need equality to treat two None values as equal and compare two Some values with a supplied equality rule.

Details

• None vs None → true
• Some vs None (or vice versa) → false
• Some(a) vs Some(b) → delegates to the provided Equivalence

Example (Comparing Options)

import { Equivalence, Option } from "effect"

const eq = Option.makeEquivalence(Equivalence.strictEqual<number>())

console.log(eq(Option.some(1), Option.some(1)))
// Output: true

console.log(eq(Option.some(1), Option.some(2)))
// Output: false

console.log(eq(Option.none(), Option.none()))
// Output: true

Signature

declare const makeEquivalence: <A>(isEquivalent: Equivalence.Equivalence<A>) => Equivalence.Equivalence<Option<A>>

Source

Since v4.0.0