effect-io-ai

Package: effect
Module: Newtype

Newtype.makeReducer

Lifts a Reducer for the carrier type into a Reducer for the newtype.

When to use

Use when you need to reduce a collection of newtype-wrapped values with the carrier’s reducer, without manually unwrapping.

Details

The returned reducer delegates to the provided carrier reducer.

Example (Reducing newtypes)

import { Newtype, Reducer } from "effect"

interface Score extends Newtype.Newtype<"Score", number> {}

const sum = Reducer.make<number>((a, b) => a + b, 0)
const reducer = Newtype.makeReducer<Score>(sum)
const iso = Newtype.makeIso<Score>()

const total = reducer.combineAll([iso.set(1), iso.set(2), iso.set(3)])
Newtype.value(total) // 6

See

• makeCombiner — lift a Combiner for the carrier

Signature

declare const makeReducer: <N extends Newtype.Any>(reducer: Reducer.Reducer<Newtype.Carrier<N>>) => Reducer.Reducer<N>

Source

Since v4.0.0