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3940 :: Field strVal cannot be found

• alexsad (orginal) [2018-06-18T16:14:53+02:00] view original

  Hi All!

  could you please look on it:

  import macros
  
  macro testM(): untyped =
    let smbl = nskLet.genSym("testLet")
    echo smbl.symbol.getImpl.strVal #comple time error: field 'strVal' cannot be found
  
  
  testM()
  Run

  Why error? How can I get an unique fresh symbol at compile time?

  Thanks

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• DeletedUser (orginal) [2018-06-18T18:49:59+02:00] view original

  I'm guessing what you want is to get the unique identifier, for which you can use the repr proc on a symbol.

  import macros
  
  macro test: untyped =
    let smbl = nskLet.genSym("testLet")
    let identifier = repr(smbl) # or repr(smbl.symbol)
    echo identifier
  
  test
  Run

  getImpl only works for consts or proc/method/converters, it returns the node of the thing the symbol is referring to. For example,

  import macros
  
  proc foo(a, b: int): int = a + b
  
  macro test: untyped =
    # bindSym gets a symbol from the codebase. brClosed gets it from where the macro is defined, brOpen gets it from where the macro is called
    let fooNode = bindSym("foo", brClosed)
    echo repr(fooNode.symbol.getImpl) # this will pretty print the AST of foo
  
  test
  Run

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• alexsad (orginal) [2018-06-18T21:11:57+02:00] view original

  Wow, repr of type NimNode or NimSym. That is nice! I didn't know it.

  Thanks a lot!

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