effect-io-ai

Package: effect
Module: Option

Option.fromUndefinedOr

Converts a possibly undefined value into an Option, leaving null as a valid Some.

When to use

Use when you want to treat only undefined as absent while preserving null as a meaningful value.

Details

• undefined → None
• Any other value (including null) → Some

Example (Converting possibly undefined values to an Option)

import { Option } from "effect"

console.log(Option.fromUndefinedOr(undefined))
// Output: { _id: 'Option', _tag: 'None' }

console.log(Option.fromUndefinedOr(null))
// Output: { _id: 'Option', _tag: 'Some', value: null }

console.log(Option.fromUndefinedOr(42))
// Output: { _id: 'Option', _tag: 'Some', value: 42 }

See

• fromNullishOr to treat both null and undefined as absent
• fromNullOr to only treat null as absent

Signature

declare const fromUndefinedOr: <A>(a: A) => Option<Exclude<A, undefined>>

Source

Since v4.0.0