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10110 :: How to inverse set?

• alexeypetrushin (orginal) [2023-04-18T12:23:14+02:00] view original

  Is that possible?

  let s = {'a'..'z'}
  echo s.inverse # ?
  Run

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• PMunch (orginal) [2023-04-18T12:36:36+02:00] view original

  Yes, you have this https://nim-lang.github.io/Nim/setutils.html#complement%2Cset%5BT%5D

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• adokitkat (orginal) [2023-04-18T12:38:22+02:00] view original

  You can do something like:

  let u8 = {char(0)..char(255)}
  let s = {'a'..'z'}
  echo u8 - s
  Run

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• shirleyquirk (orginal) [2023-04-18T18:04:29+02:00] view original

  P.S. The char set is stored as 256 bit vector right?

  Yes,

  sizeof({'a'..'z'}) == 32

  But

  sizeof(set['a'..'z']) == 4

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• cblake (orginal) [2023-04-19T00:22:52+02:00] view original

  The name in mathematics is "set complement" not "inverse" and there is a func in a stdlib module for this:

  import std/setutils
  echo complement({'a'..'z'})
  Run

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