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Haskell中具有功能的映射列表

[英]Mapping list with function in Haskell

I am new to Haskell and I'm trying to change the position of a drawn path. 我是Haskell的新手,正在尝试更改绘制路径的位置。

let redPath =  Path[Point 420 750, Point 420 550] red Solid

drawPicture 10 [redPath, movePictureObject (Vector 100 100)
redPath]

The functions movePictureObject and movePoint should change every point of the path with a given vector (100,100). 函数movePictureObject和movePoint应该使用给定的向量(100,100)更改路径的每个点。

movePoint :: Point -> Vector -> Point
movePoint (Point x y) (Vector xv yv)
  = Point (x + xv) (y + yv)

movePictureObject :: Vector -> PictureObject ->PictureObject
movePictureObject vec (Path points colour lineStyle) 
  = Path map (movePoint (points vec)) red Solid

I am not sure of how to use the map function properly, I have read several posts here and watched other tutorials. 我不确定如何正确使用map函数,我在这里阅读了几篇文章,并观看了其他教程。

Thank you. 谢谢。

我的水晶球告诉我,您只需要在最后一行中(map movePoint (points vec))而不是map (movePoint (points vec))

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