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6199 :: Macros - organizing code

• mantielero (orginal) [2020-04-12T11:05:55+02:00] view original

  I don't have much practise with macros and I normally end-up with big ones. How can I split macros bearing in mind that I might need to reference identifiers from one sub-macro into another submacro?

  mymacro:
     submacro1:
        ...
     submacro2:
        ...
     submacro3:
        (here I might need references to identfiers created in submacro1)
  Run

  Any project (simple) that I might look for inspiration?

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• mratsim (orginal) [2020-04-14T01:12:27+02:00] view original

  If you want to split a big macros in multiple macros the easiest way to do that is to use a var MyTable: Table[string, NimNode] {.compileTime.} that will collect code fragment from one macro to another.

  Simple example to transfer data between 2 macros when a seq suffices at:

  • Parsing: https://github.com/mratsim/constantine/blob/2f839cb1/constantine/config/curves_parser.nim#L115-L117
  • Code generation: https://github.com/mratsim/constantine/blob/2f839cb1/constantine/config/curves_parser.nim#L227

  More complex but still simple example: https://github.com/mratsim/Synthesis/blob/b8fdd103/synthesis/factory.nim#L77 All macros are updating the Registry object and the one that does the final code generation just read from it this way there is no interleaving.

  Maybe I should call that the Registry pattern.

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• mantielero (orginal) [2020-04-14T19:31:46+02:00] view original

  Thanks. That was what I was looking for.

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