caiorss

Debugging in Haskell's GHCi

• Enter GHCi (via Stack)

stack ghci

• Enable functions to break on exceptions

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{-# LANGUAGE ScopedTypeVariables #-}
module Main where

import Network (listenOn, withSocketsDo, accept, PortID(..), Socket)
import Control.Concurrent (forkIO)
import Control.Exception (handle, IOException)
import Control.Monad (liftM)
import System.IO (hSetBuffering, hPutStr, hClose, hGetContents, BufferMode(..), Handle, readFile)
import Debug.Trace

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import System.IO 
import Network.Socket
import Network (PortID(..))
import System.Environment
import Control.Concurrent
import Control.Monad
import Control.Monad.Fix (fix)
import Data.Char
import Data.List.Split
import System.IO.Error

caiorss

[Haskell Cheat Sheets] (https://gist.github.com/vpayno/0a7db3ff9a4fac8774c5)

By Victor Payno

Functions

Rules

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Haskell Style Guide

This is a short document describing the preferred coding style for this project. I've tried to cover the major areas of formatting and naming. When something isn't covered by this guide you should stay consistent with the code in the other modules.

Formatting

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import Control.Concurrent
import Control.Exception


setInterval :: Int -> a -> (a -> IO a) -> IO ()
setInterval microsecs a action = do
    mvar <- newEmptyMVar
    _ <- setInterval' microsecs a mvar action
    takeMVar mvar

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{-# OPTIONS_GHC -Wall -fno-warn-unused-binds #-}
{-# LANGUAGE CPP                 #-}
{-# LANGUAGE FlexibleContexts    #-}
{-# LANGUAGE IncoherentInstances #-}
{-# LANGUAGE RankNTypes          #-}
{-# LANGUAGE ScopedTypeVariables #-}

#if __GLASGOW_HASKELL__ >= 708
{-# LANGUAGE RoleAnnotations     #-}
#endif

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{-------------------------------------------------------------------------------
  Discussion of ContT in terms of callbacks

  For an alternative exposition, see
  <http://www.haskellforall.com/2012/12/the-continuation-monad.html>.
-------------------------------------------------------------------------------}

{-# OPTIONS_GHC -Wall #-}

import Control.Exception

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{-# LANGUAGE CPP                 #-}
{-# LANGUAGE FlexibleContexts    #-}
{-# LANGUAGE RankNTypes          #-}
{-# LANGUAGE ScopedTypeVariables #-}

#if __GLASGOW_HASKELL__ >= 710
{-# LANGUAGE AllowAmbiguousTypes #-}
#endif

-- | Lightweight checked exceptions

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{-# LANGUAGE TypeFamilies, KindSignatures, DataKinds, TypeOperators, GADTs, MultiParamTypeClasses, FlexibleInstances, GeneralizedNewtypeDeriving, OverlappingInstances, ScopedTypeVariables, FlexibleContexts #-}

import Control.Applicative
import Control.DeepSeq
import qualified Control.Exception as E

-- Closed type family, needs GHC HEAD.
type family Minus (e :: *) (es :: [*]) :: [*] where
  Minus e '[] = '[]
  Minus e (e ': es) = Minus e es