用符号分配列表/元组 [英] Assign Lists/Tuples with do notation

问题描述

我有一个函数f，如下所示：

I have a function f that goes something like this:

f = do
      x1 <- g
      x2 <- g
      x3 <- g
      ...
      xn <- g
      return [x1,x2,x3,..., xn] --or (x1,x2,x3,..., xn)

代码行，我有一种感觉，这可以做得更漂亮。
我想知道是否有办法做这样的事情：

This requires many lines of code and I have a feeling this can be done prettier. I would like to know if there is a way to do something like this:

f = do
      [x,y,z] <- [g,g,g]
      return [x,y,z]

推荐答案

使用 sequence 和 replicate ：

f = do
    xs <- sequence $ replicate n g
    return xs

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