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6205 :: Accessing private procs from macro in different module

• Pixeye (orginal) [2020-04-13T19:37:14+02:00] view original

  I got myself in a problem with dividing visibility of my lib, I don't want users to see any boilerplate, procs and methods they should not see.

  ### USER GAME MODULE
  import actors # engine module
  
  ComponentObject* = object
      x*,y*: int
  ComponentHealth* = object
      arg1*, arg2*: int
  ComponentPlayer* = object
      damage* : int
  
  # ecs.add is a macro
  ecs.add ComponentObject, Compact
  ecs.add ComponentPlayer, Compact
  ecs.add ComponentHealth, Compact
  
  # makes a group
  ecs.group players:
    scope: public
    comps: (ComponentPlayer, ComponentObject, ComponentHealth)
  Run

  ### ENGINE MODULE
  # decide what template to use for generating storage for a component
  macro add*(this: EcsInstance, component: untyped, component_kind: static[RegKind] = RegKind.Fast): untyped =
  
  # generating a storage for a component
  template internal_storagefast*(this: EcsBase, t: typedesc) =
  template internal_storagecompact*(this: EcsBase, t: typedesc) =
  Run

  So the thing is that I can see

  _storagefast
  Run

  and

  _storagecompact
  Run

  from the game scope. I can't make them private, cause then I can't make them work in the game module from the

   macro add
  Run

  .

  I made It impossible to work with them ( ? ) by some hacks like this

  type #@ecs
      EcsBase = object
      EcsInstance = object
          base   : EcsBase
  ecs* = EcsInstance()
  Run

  So while I can see an ECS object from the game and hit

   macro
  Run

  I can't get myself touching directly

  _storagecompact, internal_storagefast
  Run

  But It looks and feels bad :)

  The templates make some boilerplate code and stuff needed to work with components and storage. Any thoughts? : )

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• DeletedUser (orginal) [2020-04-14T01:17:00+02:00] view original

  If your macro is generating AST like ident"internal_storagecompact" then change it to bindSym"internal_storagecompact". bindSym by default uses "closed symbol scope" in contrast to "open symbol scope", as in the symbol is resolved when it's being generated in the macro rather than later. This will require internal_storagecompact to be declared before the macro though. Documentation of bindSym

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• Pixeye (orginal) [2020-04-14T06:05:34+02:00] view original

  thanks a lot :)

  bindSym("internal_storagecompact", brForceOpen)
  Run

  helped!

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