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7889 :: Would macros work to parse js and create equivalent nim code?

• xioren (orginal) [2021-04-30T08:33:34+02:00] view original

  
  function(a,b){var c=a[0];a[0]=a[b%a.length];a[b%a.length]=c}
  Run

  vvv

  proc someProc[T](a: var seq[T], b: Natural) =
    var c = a[0]
    a[0] = a[b mod a.len]
    a[b mod a.len] = c
  Run

  Is that possible?

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• Araq (orginal) [2021-04-30T08:49:38+02:00] view original

  One could do it, but the better idea is to learn and use Nim directly.

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• xioren (orginal) [2021-04-30T09:04:46+02:00] view original

  Thanks, agreed. However I am trying to write code to handle Youtubes rolling cipher which is always changing and is written in JS. So instead of going back and updating my code every time it changes I figure it would be nice to just parse it and generate the relevant nim code dynamically with macros.

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• Araq (orginal) [2021-04-30T09:08:10+02:00] view original

  Why not call the JS from Nim instead?

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• xioren (orginal) [2021-04-30T09:10:42+02:00] view original

  That's actually a really good idea. Thanks.

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• xigoi (orginal) [2021-04-30T09:17:30+02:00] view original

  Are you trying to make a YouTube client/downloader in Nim? That sounds cool!

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• xioren (orginal) [2021-04-30T19:07:27+02:00] view original

  I am! I already have a (minimal) working one, I just need to implement the cipher logic.

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• kobi (orginal) [2021-05-01T20:18:28+02:00] view original

  I see it as either parsing the page with a javascript engine and getting the result in Nim, or compiling Nim code to Js, and within Nim getting the code, handling it, etc. iow, the dynamic implementation of the rolling cipher will be used only at runtime, but all the surrounding details can be coded in nim. (you have access to dom, etc)

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