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2914 :: Is it possible to use pragma {.async.} on a generic proc?

• cdunn2001 (orginal) [2017-04-16T18:46:08+02:00] view original

  proc runParent*[TArg,TResult](arg: TArg): Future[TResult] {.async.} =
    var retFuture = asyncdispatch.newFuture[TResult]("multiproc.runParent")
    var call_result: TResult = ...
    asyncdispatch.complete(retFuture, call_result)
    return retFuture
  Run

  
  lib/pure/asyncmacro.nim(308, 7) Hint: Processing runParent as an async proc. [User]
  main.nim(15, 40) template/generic instantiation from here
  multiproc.nim(137, 3) Warning: shadowed identifier: 'result' [ShadowIdent]
  main.nim(15, 40) template/generic instantiation from here
  multiproc.nim(158, 10) Error: type mismatch: got (Future[system.int], Future[system.int])
      return retFuture
             ^
  Run

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• cdunn2001 (orginal) [2017-04-16T20:03:22+02:00] view original

  Apparently, if I add {.async.}, then I must treat result as type T instead of type Future[T]. But I still get error (plus the same ShadowIndent warning):

  multiproc.nim(141, 3) Warning: shadowed identifier: 'result' [ShadowIdent]
  main.nim(15, 40) template/generic instantiation from here
  lib/pure/asyncmacro.nim(41, 25) Error: attempting to call undeclared routine: 'callback='
              next.callback = cb
  Run

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• cdunn2001 (orginal) [2017-04-16T20:11:50+02:00] view original

  Oh. In switching to {.async.}, I need some other symbols from asyncdispatch. I usually try:

  from asyncdispath import nil
  Run

  But a normal (namespace-polluting) import makes my example work fine.

  Nvm.

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