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7637 :: Question about Macros and AST Documentation

• lotzz (orginal) [2021-03-16T04:34:08+01:00] view original

  Just a simple question. Is there any kind of documentation about what type of children NimNodes expect?

  dumpAstGen:
    type test = object
  Run

  gives the result

  nnkStmtList.newTree(
    nnkTypeSection.newTree(
      nnkTypeDef.newTree(
        newIdentNode("test"),
        newEmptyNode(),
        nnkObjectTy.newTree(
          newEmptyNode(),
          newEmptyNode(),
          newEmptyNode()
        )
      )
    )
  )
  Run

  In regards to the nnkObjectTy statement It is unclear about what should be replaced for the three newEmptyNode() calls. I know you can just try different patterns, but it would be nice if I could just know what it expects or what is possible.

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• ElegantBeef (orginal) [2021-03-16T04:38:38+01:00] view original

  I suggest writting the desired input/output and then work you way from one to the other. I mostly use dumptree for this as it tells you what's needed and then you can programatically get there. I recommend this macro writeup to see atleast my process.

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• ynfle (orginal) [2021-03-16T09:51:26+01:00] view original

  The macros module documentation has most of the information that you'd need. Here is the section on a type declaration.

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