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2880 :: New bie: tuple of fixed length arrays

• cdome (orginal) [2017-03-22T17:06:54+01:00] view original

  Apologies, if it is a too simple question.

  Is it possible define a tuple of fixed length arrays such that every array could store a different type, but have the same length. Enforce at compile that all fixed length arrays were of the same length.

  Structure that replicates column-oriented SQL table.

  Many thanks to the authors of the language, I am impressed.

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• stisa (orginal) [2017-03-22T17:47:28+01:00] view original

  Since arrays need to have a know length at compilè time, a tuple of arrays is simply:

  type
    A = tuple
      ints:array[3,int] # an array that contains 3 integers
      strings:array[3,string] # 3 strings
  
  var
    arrint = [1,2,3]
    arrstr = ["one","two","three"]
    
    a : A = (ints:arrint, strings:arrstr)
  
  echo a.ints[0] # 1
  echo a.strings[0] # one
  Run

  Is this what you meant? Obviusly you can't change the array lenght at runtime, but you can overwrite elements in the arrays. Also, is there a reason you specifically want a tuple and not an object?

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• def (orginal) [2017-03-22T18:09:53+01:00] view original

  Here:

  type MyTable[T: static[int]] = tuple[ints: array[T, int], strings: array[T, string]]
  var t: MyTable[3] = (ints: [1, 2, 3], strings: ["one", "two", "three"])
  Run

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• cdome (orginal) [2017-03-22T18:20:06+01:00] view original

  Thanks a lot!

  MyTable[T: static[int]]
  Run

  was the missing part of the puzzle.

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