effect-io-ai

Package: effect
Module: Option

Option.as

Replaces the value inside a Some with the specified constant value, leaving None unchanged.

Details

This function transforms an Option by replacing the value inside a Some with the given constant value b. If the Option is None, it remains unchanged.

This is useful when you want to preserve the presence of a value (Some) but replace its content with a fixed value.

Example

import { Option } from "effect"

// Replacing the value of a `Some`
const someValue = Option.some(42)

console.log(Option.as(someValue, "new value"))
// Output: { _id: 'Option', _tag: 'Some', value: 'new value' }

// Replacing a `None` (no effect)
const noneValue = Option.none<number>()

console.log(Option.as(noneValue, "new value"))
// Output: { _id: 'Option', _tag: 'None' }

Signature

declare const as: { <B>(b: B): <X>(self: Option<X>) => Option<B>; <X, B>(self: Option<X>, b: B): Option<B>; }

Source

Since v2.0.0