1. State
2009 5 31 id:hiratara

2. •
• State

3. • URI Comparable
Interface
Comparable
URI

4. (1)

5. Bool length
Float fst
Integer take
MyType zip
(Int, Bool) myfunc
[Char] id
Maybe String ...
Int → Int → Int
...

6. Bool length
Float fst
Integer take
MyType zip
(Int, Bool) myfunc
[Char] id
Maybe String ...
Int → Int → Int
...

7. Bool length
Float fst
Integer take
MyType zip
(Int, Bool) myfunc
[Char] id
Maybe String ...
Int → Int → Int
...

8. id
f -> f quot;abcquot; [Char]
id head
[Char] -> [Char] Char id
length
take
Int id

9. id
f -> f quot;abcquot; [Char]
id head
[Char] → [Char] Char id
length
take
Int id

10. (2)

11. :
Maybe
[Char] Maybe [Char]
Maybe
length liftM length
Maybe
Int Maybe Int

12. []
[Char] [ [Char] ]
[]
length liftM length
[]
Int [ Int ]

13. [] [Char]
[]
[Char] [ [Char] ]
[]
length liftM length
[]
Int [ Int ]

14. liftM Maybe
[]
[Char] [ [Char] ]
[]
length liftM length
[]
Int [ Int ]

15. (3) return

16. :
Maybe
return
[Char] Maybe [Char]
return
Int Maybe Int

17. []
return
[Char] [ [Char] ]
return
Int [ Int ]

18. return
State
return
[Char] State [Char]
return
Bool State Bool
return
MyType State MyType
return
IO String State (IO String)

19. (4) (>>=)

20. Maybe
[Char] Maybe [Char]
func
Int Maybe Int
Maybe

21. (>>=)
Maybe
[Char] Maybe [Char]
(>>=)
func (=<<) func
Int Maybe Int
Maybe

22. State
(>>=)
[Char] State [Char]
func1
(=<<) func1
(>>=)
Int State Int
func2
(=<<) func2
MyType State MyType

23. return
IO
[Char] IO [Char]
length
return
Int IO Int

24. IO
[Char] IO [Char]
return . length
length
return
Int IO Int

25. (>>=) liftM
IO
[Char] (>>=) IO [Char]
return . length
length (=<<) $ return . length
return
Int IO Int

26. •
• return
• (>>=)

27. •
•
• State

28. • Haskell Kleisli triple
Monad
• Kleisli triple Monad
• Kleisli triple liftM
( Monad
)