kazu-yamamoto

module TypeChecker where

type Vname = String

data Vexp = Var Vname
          | Lambda Vname Vexp
          | Ap Vexp Vexp
          | Let [Vname] [Vexp] Vexp
          | Letrec [Vname] [Vexp] Vexp

kazu-yamamoto

{-# LANGUAGE OverloadedStrings #-}

import Data.ByteString (ByteString)
import qualified Data.ByteString as B
import Data.ByteString.Char8 ()

import Data.Text (Text)
import qualified Data.Text as T

foo :: String -> Int

kazu-yamamoto

{-# OPTIONS_GHC -fno-warn-missing-signatures #-}
module Spec (main) where
import           Test.HUnit
import           System.Process
import           System.IO

subprocess = concat $
  [ "module Main where\n"
  , "import System.IO\n"
  , "main = do\n"

kazu-yamamoto

-- ghc Main.hs -package ghc

module Main where

import DynFlags
import FastString
import HsSyn
import Lexer
import Outputable
import Parser

kazu-yamamoto

PFDS: Ex 3.1

定理：

    Leftistヒープ T において、右のパスの長さが k である場合、
    T のノード数 n は
       n >= 2^(k+1) - 1
    である。

証明：T の高さである h について帰納法で証明する。

kazu-yamamoto

module Merge where

merge :: (Ord a) => [a] -> [a] -> [a]
merge xs [] = xs
merge [] ys = ys
merge l@(x:xs) r@(y:ys) 
  | x < y     = x: merge xs r
  | otherwise = y: merge l ys

msort :: Ord a => [a] -> [a]

kazu-yamamoto

import Data.Map
import Prelude hiding (lookup)

primes :: [Integer]
primes = sieve [2..]

sieve :: [Integer] -> [Integer]
sieve xs = sieve' xs empty

sieve' :: [Integer] -> Map Integer [Integer] -> [Integer]

kazu-yamamoto

function-data/relation mapper

スキーマ

table mail {
    id int primary key,
    from_addr varchar[50],
    date datetime,
    mailbox varchar[50]

}