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Chris Lynch Decoherence

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Decoherence / Scotty_Lucid_PostgreSQL.hs
Last active May 16, 2023 01:45
Haskell: Simple REST example. Process request, retrieve data from PostgreSQL backend, and respond with programmatically-generated HTML.
{-# LANGUAGE OverloadedStrings #-}
import Control.Applicative
import Control.Monad
import Control.Monad.Trans
import Data.Monoid
import Data.Text
import Database.PostgreSQL.Simple
import Database.PostgreSQL.Simple.FromRow
import Lucid
import Web.Scotty
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Decoherence / ReaderT_and_WriterT.hs
Last active August 2, 2022 02:26
Haskell: Monad Transformers -- Combine ReaderT and WriterT
-- | Main entry point to the application.
module Main where
import Control.Monad.Reader
import Control.Monad.Writer
{-
The ReaderT transformer is used to retrieve a read-only value from some environment.
The WriterT transformer will log the result of each retrieval.
Running the two transformers together yields a log of each step along with the actual results.
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Decoherence / Servant_JSON_API.hs
Last active January 17, 2020 13:07
Haskell: Bookstore REST API with PostgreSQL backend using Servant
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeOperators #-}
import Control.Applicative
import Control.Monad.IO.Class
import Data.Aeson
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Decoherence / keybase.md
Created February 8, 2016 15:18

Keybase proof

I hereby claim:

  • I am Decoherence on github.
  • I am qubitcoder (https://keybase.io/qubitcoder) on keybase.
  • I have a public key whose fingerprint is B2E9 8F37 4D4D 66AB 4AB5 CDCC 3ECE E817 6FFD C6C0

To claim this, I am signing this object:

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Decoherence / TicTacToe.hs
Last active August 29, 2015 14:19
Haskell: Tic-Tac-Toe console-based game
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE RankNTypes #-}
import Control.Monad
import Data.Char
import Data.List
import Data.List.Split
import Data.Map (Map)
import qualified Data.Map as Map
import Text.Read
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Decoherence / TypeSafeRocket.hs
Last active August 29, 2015 14:19
Example: Type-safe rocket launch using the Either monad transformer.
module Main where
import Control.Monad.Trans
import Control.Monad.Trans.Either
import Safe
data Sensor = Temp
| Fuel
| Pressure
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Decoherence / Spock_PostgrSQL_Users.hs
Last active August 29, 2015 14:19
Haskell: Testing Spock web server using PostgreSQL backend and the 'users' library for user management & session handling.
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE DeriveGeneric #-}
module Main where
import Database.PostgreSQL.Simple
import Data.Aeson hiding (json)
import Data.Monoid
import Data.Text (pack)
import GHC.Generics
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Decoherence / PrimeNumbers.hs
Last active August 29, 2015 14:19
Command-line utility to quickly generate prime numbers (Haskell)
import Control.Applicative
import Control.Monad
import Options
import Safe
{-
Command-line arguments:
-m: biggest prime less than m (required)
-l: show full list (optional)
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Decoherence / View_Patterns_Demo.hs
Last active August 29, 2015 14:16
Fun with View Patterns: Calculate bonus points for a customer based on their reward status
{-# LANGUAGE ViewPatterns #-}
module Main where
data Status = Silver
| Gold
| Platinum
deriving (Show)
type Points = Int
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Decoherence / JSON_Lens_Auto_Derive.hs
Last active August 29, 2015 14:16
Haskell JSON: Demonstrates how to automatically derive JSON instances for easy encoding/decoding of a nested data record. Also construct lenses for easy viewing/modification of fields.
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE TemplateHaskell #-}
import Control.Lens
import Data.Aeson
import qualified Data.ByteString.Lazy.Char8 as C
import GHC.Generics
-- For production code, use Text instead of String
data Person = Person { _personName :: String
, _personAge :: Int