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6764 :: Regex replace with callback?

• ElAfalw (orginal) [2020-09-03T08:05:33+02:00] view original

  In Ruby there is a way to replace occurences of a given regular expression with the value returned by a callback.

  For example:

  
  s.gsub(/^\d+(\w+)\d+/) {
        |m| m.upcase
  }
  Run

  which basically takes every "word", surrounded by digits, passes it to the callback function, gets it uppercased and replaces the original.

  How can I do something like that in Nim?

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• xigoi (orginal) [2020-09-03T11:30:33+02:00] view original

  It seems that the regex package supports this.

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• shirleyquirk (orginal) [2020-09-03T11:37:09+02:00] view original

  Definitely spend some time reading through the docs for nre, I haven't used it much but was able to cobble this together

  import nre,strutils
  
  proc upcase(r:RegexMatch):string = r.captures[0].toupperAscii()
  
  let input = "4four4 score and 7seven7"
  
  echo replace(input,re"\d+(\w+)\d+",upcase) #FOUR score and SEVEN
  Run

  I also don't know ruby but I think that's what you're going for, for each match, replace it with the captured (w) raised to upper case

  If you want to leave the numbers in there, the callback would return r.match.toUpperAscii() instead

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