yashigani

struct User {
    let username: String
}

extension User: CustomStringConvertible {
    var description: String { return "username: \(username)" }
}

// DAO

yashigani

#import <UIKit/UIKit.h>

@interface MyPickerView : UIView
<UIPickerViewDataSource, UIPickerViewDelegate>
{
    UIToolbar *toolbar;
    UIPickerView *picker;

    void (^completion)(NSString *selected);

yashigani

#import <Foundation/Foundation.h>

@interface YSNetwork : NSObject
@property (readonly) NSURL *URL;
@property (strong, nonatomic) NSURLRequest *request;
@property (strong, nonatomic) NSString *userAgent;
@property (strong, nonatomic, readonly) NSData *responseData;
@property (strong, nonatomic, readonly) NSDictionary *responseHeader;
@property (strong, nonatomic) void (^completion)(NSDictionary *responseHeader, NSData *responseData);
@property (strong, nonatomic) void (^failure)(NSError *error);

yashigani

import System.Environment (getArgs)
import Data.Char (digitToInt)

spare = (==) '/'
strike = (==) 'X'

updateBonus r (b1, b2)
    | spare r = (b2 + 1, 0)
    | strike r = (b2 + 1, 1)
    | otherwise = (b2, 0)

yashigani

import System.Environment (getArgs)

main = do
    (x:_) <- getArgs
    mapM_ putStrLn $ createFizzBuzz $ read x

createFizzBuzz :: Int -> [String]
createFizzBuzz 0 = []
createFizzBuzz x = map fizzbuzz [1..x]

yashigani

13 モナドがいっぱい

おさらい

Functor

• 文脈を持った値に関数を適用する

  • f aに(a -> b)を適用したい

• r -> aからr -> bに

  fmap :: (Functor f) => (a -> b) -> f a -> f b

yashigani

以下の関数を定義しなさい

• null
• sum
• product
• elem
• Pythonのスライス
  • ex) slice 2 5 [1..7] # => [3, 4, 5]
• フィボナッチ数列のn番目の数を返す関数
• FizzBuzzのn項目からm項目までを返す関数

yashigani

import System.Environment (getArgs)
import Prelude hiding (head, tail)
import Data.Char (ord)

sudden :: String -> String
sudden s = unlines [head s, body s, tail s]

body :: String -> String
body s = "＞　突然の" ++ s ++ "　＜"

yashigani

すごいH本読書会 #7

8章 入出力

Hello, world

そのまえに...

入出力(I/O)の基本

• I/Oアクションとは何か？
• I/Oアクションはどう入出力を可能にするか？

yashigani

data Akari a = Waai a (Akari a) | Daisuki deriving (Show)
data H oo gle = H oo oo oo oo oo gle deriving (Show)
data Ha y oo = Ha y oo oo oo oo oo deriving (Show)
data O b = OOOO|OOOOOO|O|OO deriving (Show)
data Hom r a = Hom (r -> a)
data State s a = State (s -> (a, s))
data Just a = Nothing | Maybe (Maybe a)

instance Functor Akari where
    fmap _ Daisuki = Daisuki