Haskellの関数の動作チェック4

関数の使い方メモ

動作環境
GHCi, version 7.6.3

concat関数

Prelude Data.List> concat ["a", "b", "c", "d"]
"abcd"
Prelude Data.List> concat [[1,5], [2,6], [3,7], [4,8]]
[1,5,2,6,3,7,4,8]

concatMap関数

Prelude Data.List> concat $ (map (\x -> show x) [1, 2, 3, 4])
"1234"
Prelude Data.List> concatMap(\x -> show x) [1,2,3,4] == concat((map(\x -> show x) [1,2,3,4]))
True

and関数

Prelude Data.List> and [True, True, False]
False
Prelude Data.List> and [True, True, True]
True
Prelude Data.List> and $ map even [2, 4, 6, 8]
True

or関数

Prelude Data.List> or [False, False, False]
False
Prelude Data.List> or [False, False, True]
True
Prelude Data.List> or $ map odd [2,4,6,8]
False
Prelude Data.List> or $ map odd [2,4,6,8,9]
True

any関数

Prelude Data.List> any (==0) [1..10]
False
Prelude Data.List> any (==0) [-1..10]
True

all関数

Prelude Data.List> all (/=0) [-1..10]
False
Prelude Data.List> all (/=0) [1..10]
True