shajra

def tryIt[F[_] : MonadError[String, ?[_]] : MonadState[Int, ?[_]]] = {
  val attempt =
    for {
      _ <- 1.put[F]
      _ <- "oh noes".raiseError[F, Unit]
    } yield ()
  attempt.handleError(_ => ().pure[F])
}

def tryItSE =

shajra

{
    packageOverrides = super: rec {
        /*
        haskell = super.haskell // {
            compiler = super.haskell.compiler // {
                ghc801 = super.stdenv.lib.overrideDerivation super.haskell.compiler.ghc801 (oldAttrs: {
                    patches = oldAttrs.patches ++ [./ghc.801.patch];
                });
            };
        };

shajra

$ nix-build -E '
    let n = import <nixpkgs> {}; hp = n.haskellPackages; l = n.haskell.lib;
    in hp.aeson
'  # MAKES HADDOCK
/nix/store/rxny4hw6m5hxs69pl27n48whyizx1f1y-aeson-0.11.3.0

$ nix-build -E '
    let n = import <nixpkgs> {}; hp = n.haskellPackages; l = n.haskell.lib;
    in l.dontHaddock (l.doHaddock hp.aeson)
'  # MAKES HADDOCK

shajra

source "$stdenv/setup"


mkdir -p "$out/bin"
cp "$src/strings-replace" "$out/bin"
wrapProgram "$out/bin/strings-replace" \
    --prefix PATH : "${binutils}/bin" \
    --prefix PATH : "${coreutils}/bin" \
    --prefix PATH : "${gnugrep}/bin"

shajra

{-# LANGUAGE TemplateHaskell #-}


module ClassyPrisms where


import Control.Lens.TH (makeClassyPrisms)


data Foo = FooA | FooB

shajra

{-# LANGUAGE FlexibleInstances          #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE KindSignatures             #-}
{-# LANGUAGE MultiParamTypeClasses      #-}
{-# LANGUAGE NoImplicitPrelude          #-}
{-# LANGUAGE TemplateHaskell            #-}
{-# LANGUAGE TypeFamilies               #-}
{-# LANGUAGE UndecidableInstances       #-}

shajra

{-# LANGUAGE NoImplicitPrelude #-}


module C12E.Exceptions where


import Protolude hiding (catch, onException, uninterruptibleMask)

import Control.Monad.Except (MonadError(catchError, throwError))
import Control.Monad.Catch (MonadMask, uninterruptibleMask)

shajra

#!/usr/bin/env stack
-- stack --install-ghc runghc --package safe-exceptions --package lens --package mtl


{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE ConstraintKinds #-}
{-# OPTIONS_GHC -Wall -Werror #-}


import Control.Exception (IOException)

shajra

{-# LANGUAGE
    FlexibleInstances
    , GeneralizedNewtypeDeriving
    , NoImplicitPrelude
    , OverloadedStrings
    , RankNTypes
#-}


module C12E.Validation.ReadV where

shajra

trait Translate[A, B] {
  def apply(a: A): B
}


trait TranslateSyntax {
  implicit class TranslateOps[A](a: A) {
    def translate[B](implicit tr: Translate[A, B]): B = tr(a)
  }
}