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7443 :: Immutable vs mutable

• vinyll (orginal) [2021-01-29T10:51:45+01:00] view original

  Hey all!

  I've been using Nim for a week now and starting to be able whatever I need. I used to do PHP for 10y, then moved to Python and JavaScript for 10y also and now discovering Nim.

  Reasons I left these languages is for getting one that is strong typing, and also to get more logic into functions.

  Nim seemed to be a good choice, though I find some WTF in the language; therefore I must probably miss some light, hence this question :)

  strutils.strip and strutils.stripLineEnd seem quite close with each their specific action. However one is immutable, and the other mutes the string.

  
  let readFile("content.txt").strip
  Run

  -> ok

  
  let readFile("content.txt").stripLineEnd
  Run

  -> error

  We should change the writing to

  
  var content = readFile("content.txt")
  content.stripLineEnd
  Run

  I find it quite incoherent as I did in previous languages. What is the logic behind this? Do you agree with this behavior?

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• lqdev (orginal) [2021-01-29T10:55:42+01:00] view original

  Currently, strutils is quite inconsistent with its usage of var vs non-var strings, mostly due to its age. You can always use dup to make stripLineEnd outplace:

  import std/sugar  # for dup
  let content = readFile("content.txt").dup(stripLineEnd)
  Run

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• vinyll (orginal) [2021-01-29T12:39:47+01:00] view original

  I'm reassure to read that the feeling of inconsistency is shared and that there's a workaround. Do you know if it's planned to be _fixed as the language is quite mature now, or is it _as is for all languages?

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• doofenstein (orginal) [2021-01-29T12:49:20+01:00] view original

  dup isn't really a workaround and more of a solution to the problem, it just was a relatively late addition. See https://github.com/nim-lang/RFCs/issues/193

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