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10669 :: Can someone tell me how to read the AST associated with a varaible?

• ggb-sw1 (orginal) [2023-11-22T19:24:35+01:00] view original

  If I have a statement such as:

  let val = "test text"
  Run

  Then how can I get the AST for val?

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• Isofruit (orginal) [2023-11-22T19:37:16+01:00] view original

  For the actual AST as in the code, use dumpAstGen from std/macros:

  import std/macros
  
  dumpAstGen:
    let val = "test text"
  Run

  For a more readable representation that is very similar but not directly usable code, use dumpTree from the same lib:

  import std/macros
  
  dumpTree:
    let val = "test text"
  Run

  Note, that for clarification: That is the AST of the entire statement.

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• SolitudeSF (orginal) [2023-11-22T19:56:44+01:00] view original

  https://nim-lang.org/docs/macros.html#getImpl%2CNimNode

  macro getBody(a: typed): untyped =
    echo a.getImpl.repr
  Run

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• ggb-sw1 (orginal) [2023-11-22T21:55:10+01:00] view original

  As you say, what that does is print the statement AST.

  What I am really trying to do is get the NimNode value for val, and be able to programmatically interrogate it.

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• PMunch (orginal) [2023-11-22T22:09:07+01:00] view original

  So you want a macro. Either write one which takes a single argument of type untyped or typed and the call it like e.g. dumpTree from above. Or simply extend the code given by SolitudeSF, the call to getImpl gets you the NimNode you require.

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