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8726 :: What approach can I use to fix a number of parameters in some functions?

• mantielero (orginal) [2021-12-19T15:23:15+01:00] view original

  First sorry for the thread's subject, but I don't know how to explain it well.

  I have several functions that follow a pattern simular to this:

  
  proc fname(sys:var System; param1:P1; param2:P2; .....; wp:Workplane; grp:Group):Whatever =
     ....
  Run

  But once known sys, wp and grp, I would like to use: proc fname(param1:P1; param2:P2;...):Whatever.

  What I would like to do is to fix those params. Something similar like closures but applying to several functions.

  I was thinking about using a global for sys, and setting something default values for wp and grp. But I don't like it that much.

  I was also thinking on templates or macros.

  Is there any simpler approach that comes to your minds? Thanks

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• aEverr (orginal) [2021-12-19T15:28:13+01:00] view original

  https://nim-lang.org/docs/manual.html#statements-and-expressions-using-statement

  excerpt:

  using
    c: Context
    n: Node
    counter: int
  
  proc foo(c, n) = ...
  proc bar(c, n, counter) = ...
  proc baz(c, n) = ...
  
  proc mixedMode(c, n; x, y: int) =
    # 'c' is inferred to be of the type 'Context'
    # 'n' is inferred to be of the type 'Node'
    # But 'x' and 'y' are of type 'int'.
  Run

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• mantielero (orginal) [2021-12-19T15:32:08+01:00] view original

  But it looks like using simplifies the definition of the functions. I am looking to simplify the way in which I use the functions.

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• ynfle (orginal) [2021-12-19T15:49:08+01:00] view original

  Either with default parameters or overloading the function definition. Check the manual (https://nim-lang.org/docs/manual.html) for these.

  My guess is you come from a dynamic language like python, ruby, javascript

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• planetis (orginal) [2021-12-19T16:15:43+01:00] view original

  You can use templates

  template fname: untyped = fname(sys, p1, p2)
  Run

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• enthus1ast (orginal) [2021-12-19T17:47:40+01:00] view original

  Why not create a new type that holds these objects and pass this to the procs?

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• kobi (orginal) [2021-12-19T19:46:52+01:00] view original

  You can have setGrp, setWp, on System object. they can be saved in that type, and then you use the more flexible parameters... if I understood your usecase. I think that's the best way. other options are a singleton or an external json etc. just some ideas. i think the first solution is the most straightforward one, but I am not sure what you are exactly trying to achieve, so it could be off.

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• mantielero (orginal) [2021-12-19T20:38:32+01:00] view original

  I think this is what makes me feel more confortable. Thank you eveybody for the sugestions.

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