小编Sir*_*ack的帖子

我正在尝试编写一个返回给定数字下所有素数列表的过程.

例如:

Prelude>primes 8  
[2,3,5,7]  

当我尝试加载文件时,Parse error in pattern Failed, modules loaded: none.如果有人能指出我正确的方向,我将不胜感激.

primes :: Int -> [Int]
primes x < 2 = []
primes x | isPrime x == True = primes (x - 1) ++ x
         | otherwise = primes (x - 1)

isPrime :: Int -> Bool
isPrime x | x < 2 = False
          | x == 2 || x == 3 = True
          | divEven x == True = False
          | divOdd x …