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9870 :: 大家好,有没有类似foldlIt的功能

• fzqdoo (orginal) [2023-02-06T10:36:17+01:00] view original

  Hello everyone, is there a function similar to foldlIt

  var numbers = @[1, 2, 3]
  echo foldl(numbers, a+b)
  This works fine and is equal to 6
  Run

  But the following compiles and reports an error

  type
     TWPT* = object
       x*: int
       y*: int
  
  var pts = @[TWPT(x: 0, y: 0), TWPT(x: 1, y: 1)]
  echo foldl(pts, a.x + b.x)
  #echo foldlIt(pts, a.x + b.x)
  Run

  I think there should be such a function, but I can't find a way, can someone tell me, thank you

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• PMunch (orginal) [2023-02-06T10:47:33+01:00] view original

  foldl is already a template similar to the other *It templates. It's simply named this way because it doesn't have an it symbol and there is no non-template foldl.

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• scroot (orginal) [2023-02-06T10:53:28+01:00] view original

  你终于现身了

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• fzqdoo (orginal) [2023-02-06T11:00:39+01:00] view original

  type
     TWPT* = object
       x*: int
       y*: int
  
  var pts = @[TWPT(x: 0, y: 0), TWPT(x: 1, y: 1)]
  echo foldl(pts, a.x + b.x)
  Run

  But this compilation fails, and an error is reported

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• fzqdoo (orginal) [2023-02-06T11:09:52+01:00] view original

  The zero-functional package should have such a function, but I think it should be better to have a built-in

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• DeletedUser (orginal) [2023-02-06T11:11:57+01:00] view original

  You need to do this:

  import sequtils
  
  type
     TWPT* = object
       x*: int
       y*: int
  
  var pts = @[TWPT(x: 0, y: 0), TWPT(x: 1, y: 1)]
  echo foldl(pts, a + b.x, 0)
  Run

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• fzqdoo (orginal) [2023-02-06T14:15:15+01:00] view original

  perfect, thanks

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