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2517 :: Methods at the compile time: Does it work as intended?

• xomachine (orginal) [2016-09-05T18:36:20+02:00] view original

  Hello!

  I've encountered a method related problem at the compile time. Take a look at the code:

  type
    AnimalObj* = object of RootObj
    Animal* = ref AnimalObj
    Cat* = ref object of AnimalObj
    Dog* = ref object of AnimalObj
  
  method kind(o: Animal): string {.base.} =
    "Animal"
  
  method kind(o: Cat): string =
    "Cat"
  
  method kind(o: Dog): string =
    "Dog"
  
  proc newCat*(): Cat =
    new(result)
  
  proc newDog*(): Dog =
    new(result)
  
  static:
    let animals: seq[Animal] = @[newCat(), newDog()]
    echo "Compile time:"
    for animal in animals:
      echo animal.kind().repr
  
  
  echo "Run time:"
  let rtanimals: seq[Animal] = @[newCat(), newDog()]
  for animal in rtanimals:
    echo animal.kind().repr
  
  
  Run

  After running it I've got the following result:

  
  $ nim c --run mwe.nim
   ...
  Compile time:
  ""
  ""
   ...
  Run time:
  0x7f36c62d4050"Cat"
  0x7f36c62d4078"Dog"
  
  Run

  So, looks like methods are not working at the compile time. Is it a bug?

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• bozaloshtsh (orginal) [2016-09-05T19:14:58+02:00] view original

  According to the manual, you cannot evaluate methods at compile time.

  "other optimizations like compile time evaluation or dead code elimination do not work with methods."

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