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3601 :: how to fix ambiguous call's.

• enthus1ast (orginal) [2018-03-03T12:18:22+01:00] view original

  I've got an error like this:

  
  server.nim(302, 66) template/generic instantiation from here
  server.nim(304, 54) template/generic instantiation from here
  lib/pure/asyncfutures.nim(303, 23) template/generic instantiation from here
  lib/pure/asyncfutures.nim(273, 15) Error: ambiguous call;
      both strutils.contains(s: string, sub: string)[declared in lib/pure/strutils.nim(1630, 5)] and
      flatdb.contains(key: string, val: string)[declared in /home/david/.nimble/pkgs/flatdb-0.1.1/flatdb.nim(322, 5)]
      match for: (string, string)
  Run

  strutils contains

  proc contains*(s, sub: string): bool {.noSideEffect.} =
  Run

  flatdb contains

  proc contains*(key: string, val: string): proc = ...
  Run

  My (humble) questions are:

  1. what would be the way to go to fix something like this?

     annotate any import with except?

     import strutils except contains
     Run

  2. i could rename/change the flatdb proc (but what if i could not?)
  3. could the compiler, maybe based on the return value, figure out which proc to use?
  4. how would you check which file/line in my code "really" caused the issue? Since the reference to lib/pure/asyncfutures.nim(303, 23) does not help me here?

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• dom96 (orginal) [2018-03-03T13:33:17+01:00] view original

  1. I'm not entirely sure what the purpose of your contains proc is, but you should probably fix it by creating a distinct string and having your contains proc work on that. Really, you should actually rename your contains proc to something else because contains should always return a bool, otherwise how would it work with the x in y syntax? (this uses contains!).
  2. If you could not then you can get around it by writing import flatdb except contains and then use flatdb.contains() explicitly with the module name at the front.
  3. It could, but return type overloading is something that will definitely not happen. As far as I understand it opens up a can of worms.
  4. Seems like you want to look at these: "server.nim(302, 66) template/generic instantiation from here", it's like a trail of breadcrumbs.

  Hope this helps.

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