dtchepak

class Maybe
    def self.empty
        Maybe.new nil
    end
    def initialize(value)
        @value = value
    end
    def bind(f)
        @value.nil? ? self : f.call(@value)
    end

dtchepak

// See also: http://davesquared.net/2012/12/lazy-monad-csharp.html

public static class LazyExtensions
{
    public static Lazy<TResult> Select<T, TResult>(this Lazy<T> value, Func<T, TResult> selector)
    {
        return new Lazy<TResult>(() => selector(value.Value));
    }

    public static Lazy<TResult> SelectMany<T, TResult>(this Lazy<T> value, Func<T, Lazy<TResult>> selector)

dtchepak

error FS0193: internal error: Value cannot be null.
Parameter name: con

dtchepak

    [Test]
    public void TEST()
    {
        var results = FirstResults().Concat(GetResults());

        Console.WriteLine("results created");

        Console.WriteLine("get first");
        results.First();
        Console.WriteLine("get last");

dtchepak

import Control.Arrow ((>>>))
import Data.List.Zipper
import Data.Maybe

{- ref: 
 - http://www.reddit.com/r/dailyprogrammer/comments/12qi5b/1162012_challenge_111_easy_star_delete/ 
 - -}

starDelete' :: String -> String
starDelete' []          = []

dtchepak

[Test]
public void ShouldNotReturnNullWebServiceResponse()
{
    var iv_client = Substitute.For<Client>();
    iv_client.GetValuation("G1|12345", 10000, 2008, "08").Returns(new WebServiceResponse()
    {
        Result = false,
        ErrorEnum = IdResponseCode.NoDataFound
    });

dtchepak

runKoan :: Koan -> IO Bool

runUntilFail :: [Koan] -> IO ()
runUntilFail [] = return ()
runUntilFail (x:xs) = do
    continue <- runKoan x
    when continue $ runUntilFail xs

dtchepak

randomMonth :: (RandomGen g) => State g String
randomMonth = 
    let monthNames = [ "January", "February", "March"
                     , "April", "May", "June"
                     , "July", "August", "September"
                     , "October", "November", "December"
                     ]
    in (monthNames !!) <$> randomNumber (1,11)

randomNumber :: (RandomGen g) => (Int,Int) -> State g Int

dtchepak

import Control.Monad.State
import System.Random

type Field = String

replaceField :: String -> Field -> Field
replaceField newContent field = 
    let fieldName = takeWhile (/=':') field
    in fieldName ++ ": " ++ newContent

dtchepak

randomChar :: (RandomGen g) => State g Char
randomChar = state $ randomR ('a','z')

randomStringWithLength :: (RandomGen g) => Int -> State g String
randomStringWithLength i = replicateM i randomChar

randomString :: (RandomGen g) => State g String
randomString = state $ \g ->
    let (charsToGen, g') = randomR (1,10) g
    in  runState (randomStringWithLength charsToGen) g'