{-# LANGUAGE AllowAmbiguousTypes #-} -- This Source Code Form is subject to the terms of the Mozilla Public -- License, v. 2.0. If a copy of the MPL was not distributed with this -- file, You can obtain one at https://mozilla.org/MPL/2.0/. {- | Copyright : (c) 2023 Sayo Koyoneda License : MPL-2.0 (see the file LICENSE) Maintainer : ymdfield@outlook.jp This module provides the t`Input` effect, comes from [@Polysemy.Input@](https://hackage.haskell.org/package/polysemy-1.9.1.1/docs/Polysemy-Input.html) in the @polysemy@ package. Realizes input of values from the external world. -} module Data.Effect.Input where -- | A general effect representing input of values from the external world. data Input i (a :: Type) where -- | Retrieve a value input from the external world. Input :: Input i i makeEffectF [''Input] -- | Returns the value obtained by transforming the input value using the given function. inputs :: (Input i <: f, Functor f) => (i -> a) -> f a inputs :: forall i (f :: * -> *) a. (Input i <: f, Functor f) => (i -> a) -> f a inputs i -> a f = i -> a f (i -> a) -> f i -> f a forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b <$> f i forall i (f :: * -> *). SendFOE (Input i) f => f i input