Haskell語言Prelude模塊中函數map的用法及代碼示例。
用法類型:
(a -> b) -> [a] -> [b]
返回通過將函數(第一個參數)應用到作為第二個參數傳遞的列表中的所有項而構造的列表
示例1:
輸入:
map abs [-1,-3,4,-12]
輸出:
[1,3,4,12]
示例2:
輸入:
map reverse ["abc","cda","1234"]
輸出:
["cba","adc","4321"]
示例3:
輸入:
map (3*) [1,2,3,4]
輸出:
[3,6,9,12]
示例4:
輸入:
map (recip . negate) [1,4,-5,0.1]
輸出:
[-1.0,-0.25,0.2,-10.0]
示例5:
輸入:
map (print) [1,3,5,6,7]
輸出:
[<<IO action>>,<<IO action>>,<<IO action>>,<<IO action>>,<<IO action>>]
注:本文由純淨天空篩選整理自 haskell map。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。