Innf107

#!/usr/bin/env polaris

module List = import("../polaris/lib/list.pls")

let filterMap : forall a b. (a -> < Nothing, Just(b) > , List(a)) -> List(b)
let filterMap(f, list) = match list {
    [] -> []
    (x :: xs) -> match f(x) {
        Nothing -> filterMap(f, xs)
        Just(y) -> y :: filterMap(f, xs)

Innf107

{-# LANGUAGE GHC2021, FunctionalDependencies, AllowAmbiguousTypes, OverloadedRecordDot, BlockArguments #-}
module Lib where

-- Code accompanying https://prophetlabs.de/posts/insttypes.html

import qualified Data.Map as Map

import Unsafe.Coerce

import Data.Proxy

Innf107

{-# LANGUAGE RankNTypes, PatternSynonyms, GADTs, ViewPatterns, LambdaCase, ScopedTypeVariables #-}
module Main where
    
import Data.Map as Map
import Control.Monad (ap, liftM)
import Data.IORef

data ComeFromOp a where
    Line :: Int -> ComeFromOp ()
    LiftIO :: IO () -> ComeFromOp ()