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10710 :: casting to seq[] will copy

• alireza (orginal) [2023-11-30T23:12:00+01:00] view original

  Hi, i wanted to create a seq from my own buffer but copy is happening, even with cast which is not supposed to. so are there any other way to do it?

  testing this on devel

  var str = "abc"
  prepareMutation(str)
  var sequence = cast[seq[char]](str)
  str[0] = 'x'
  echo str , " : ", sequence
  #    xbc : @['a', 'b', 'c']
  Run

  Thanks for help

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• Araq (orginal) [2023-11-30T23:19:54+01:00] view original

  The cast doesn't copy, the binding to the var does. See for yourself:

  var str = "abc"
  prepareMutation(str)
  var sequence {.cursor.} = cast[seq[char]](str)
  str[0] = 'x'
  echo str , " : ", sequence
  Run

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