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4720 :: Is it possible to add a proc after a proc in a macro?

• lqdev (orginal) [2019-03-16T15:21:11+01:00] view original

  I don't know how to put this into the right words, so let me give you an example:

  macro someTransformation(proc1: NimNode): NimNode =
    # create a "wrapper" proc for proc1
  
  proc someProc(a, b: float): float =
    result = a * 2 + a / b
  
  someTransformation(someProc) # this should create a new proc based off of someProc
  Run

  Is this possible? AFAIK someProc will be passed as an nnkIdent to someTransformation, but I need to pass the AST of the proc itself.

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• ggibson (orginal) [2019-03-16T17:59:37+01:00] view original

  I think Steve Flenniken covers this or something very close to it in his blog post about nim macros

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• lqdev (orginal) [2019-03-16T18:06:02+01:00] view original

  I already knew about the stuff he wrote, it doesn't solve my problem though.

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• ggibson (orginal) [2019-03-16T18:18:17+01:00] view original

  Then definitely check out the memo module, because it shows how you create, copy, and rename procs in a macro.

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• shashlick (orginal) [2019-03-16T20:17:56+01:00] view original

  What exactly do you want to do in someTransformation? You could just use a template if you just want to do something before or after calling the proc being passed.

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