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6816 :: expandMacros problem with export postfix star '*'

• slonik_az (orginal) [2020-09-14T21:36:56+02:00] view original

  Hello:
  Apparently, expandMacros ignores postfix star * in exportable declarations and instead of producing
  

  let fooStar* = 123 it outputs let fooStar = 123 without *. The following MWE provides the details

  ## `expandMacros` ignores export postfix `*`
  
  import macros
  
  when false: # keeping for guidance
      dumpAstGen:
          let fooStar* = 123
  
  macro mfooStar(): untyped =
      ## expands to
      ## let fooStar* = 123
      result= nnkStmtList.newTree(
                  nnkLetSection.newTree(
                      nnkIdentDefs.newTree(
                      nnkPostfix.newTree(
                          newIdentNode("*"),
                          newIdentNode("fooStar")
                      ),
                      newEmptyNode(),
                      newLit(123)
                      )
                  )
              )
  
  macro mbar: untyped =
      ## expands to
      ## let bar = 456
      result= nnkStmtList.newTree(
                  nnkLetSection.newTree(
                      nnkIdentDefs.newTree(
                      newIdentNode("bar"),
                      newEmptyNode(),
                      newLit(456)
                      )
                  )
              )
  
  when true:
      expandMacros:
          mfooStar()
          mbar()
      
      echo fooStar
      echo bar
  Run

  The resulting output from compilation 'nim c foo.nim'

  let fooStar = 123
  let bar = 456
  Run

  is missing export postfix star '*' after the fooStar symbol.

  --Leo

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• juancarlospaco (orginal) [2020-09-15T00:25:48+02:00] view original

  Make an explicit export fooStar ?.

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• slonik_az (orginal) [2020-09-15T02:01:50+02:00] view original

  mfooStar macro performs as expected and generates AST that corresponds to let fooStar* = 123. It is expandMacros that prints incorrect textual representation of this AST. I think it is a bug in expandMacros implementation.

  --Leo

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• shirleyquirk (orginal) [2020-09-15T13:45:39+02:00] view original

  it happens during the template/macro evaluation of expandMacro's body when it's being turned into a typed parameter. the nnkPostfix(nnkIdent("*"),nnkIdent("fooStar")) gets resolved to nnkSym("fooStar")

  getAst(mfooStar()).repr returns the expected string, not sure how much help that is

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• slonik_az (orginal) [2020-09-15T15:47:41+02:00] view original

  getAst(mfooStar()).repr returns the expected string, not sure how much help that is

  @shirleyquirk: Thanks for a useful suggestion! Now, whenever I want to see what source code my macro call expands to I can do

  static:
      echo getAst(mfooStar()).repr
  Run

  instead of a buggy expandMacros.

  --Leo

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