vvv

#!/usr/bin/env stack
{- stack --resolver lts-9.21 script
       --package shelly --package text
 -}
{-# OPTIONS_GHC -Wall -Werror #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ExtendedDefaultRules #-}
{-# OPTIONS_GHC -fno-warn-type-defaults #-}

import           Shelly

vvv

#!/usr/bin/env stack
-- stack --resolver lts-9.21 script --package loch-th
{-# LANGUAGE TemplateHaskell #-}
{-# OPTIONS_GHC -Wall -Werror #-}

import Debug.Trace.LocationTH (check)
import System.Environment (getArgs)

main :: IO ()
main = do

vvv

#!/usr/bin/env stack
-- stack --resolver lts-11.2 script
{-# OPTIONS_GHC -Wall -W -Werror #-}

data Foo = Foo
  { fooInt :: Int
  , fooBar :: Bar
  } deriving Show

data Bar = Bar Baz

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{-# OPTIONS_GHC -Wall -Werror #-}

module DaPhone where

import Data.Char (isUpper, toLower)
import Data.List (elemIndex, foldl', intersperse)
import Data.Maybe (catMaybes)

data DaPhone = DaPhone [String]
  deriving (Eq, Show)

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import Data.Foldable (foldl')
import Debug.Trace (trace)

prnEqual :: (Eq a) => a -> a -> IO ()
prnEqual a b = if a == b then print "True" else print "False"

-- Note the absence of parentheses around `Eq a` and having exactly one `print`.
prnEqual' :: Eq a => a -> a -> IO ()
prnEqual' a b = print $ if a == b then "True" else "False"

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{-- XXX Your definition of `checkChar` is okay, but the abstraction itself
 -- is very odd.  It is fine as an exercise of using "do" notation and
 -- `return`. In real code though explicit statements are both short and
 -- expressive (see lines 21-22).
checkChar :: IO Bool
checkChar = do
    c <- getChar
    return (c == 'y')
--}

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listsum :: Num a => [a] -> a
listsum [] = 0
listsum (x:xs) = x + listsum xs

main :: IO ()
main = print $ listsum [1..5]

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{-# LANGUAGE GADTs #-}
module Program where
--
-- The Operational Monad Tutorial:
-- http://apfelmus.nfshost.com/articles/operational-monad.html
--

-- GADT
data Program instr a where
    Then   :: instr a -> (a -> Program instr b) -> Program instr b

vvv

$ cat noexit.sh 
#!/bin/sh
seq 100 | while read; do exit; done  # If `exit' terminated the script ..
echo 'Still alive!'                  # .. this message would not be printed.
$ 
$ sh noexit.sh
Still alive!

vvv

#!/bin/sh
set -eu

M0UT=ut/.libs/lt-m0ut
[ -x $M0UT ] || { echo "$M0UT: No such file" >&2; exit 1; }

CORE=$(sudo ls -t $(sudo find /var/mero -type f -name core.\*) | head -1)

sudo gdb -nx -c $CORE $M0UT <<EOF
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