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6555 :: Printing Nim AST as Nim code?

• aviator (orginal) [2020-07-18T23:47:10+02:00] view original

  I know there is dumpTree etc, but is there any way to actually print the AST as the Nim code it represents? For example, the tree:

  
  StmtList
    Command
      Ident "echo"
      StrLit "Hello, World!"
  Run

  would print:

  echo "Hello, World!"
  Run

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• Yardanico (orginal) [2020-07-18T23:49:51+02:00] view original

  repr :)

  import macros
  
  
  macro test: untyped =
    result = nnkStmtList.newTree(
      nnkCommand.newTree(
        ident"echo", newLit("Hello, World!")
      )
    )
    echo repr result
  
  test()
  Run

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• aviator (orginal) [2020-07-18T23:57:16+02:00] view original

  Awesome, thanks!

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• Yardanico (orginal) [2020-07-19T00:14:10+02:00] view original

  Although beware - repr will show you Nim code for the AST as-is, e.g. if you have some gensym'd variables or something like that. Code pritned by repr is not guaranteed to be compilable as-is

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