anchor.diff:                  Res = all_pkgs(DepGraph, NewVisited, DepPkgs ++ OtherPkgs, UConstraints, PathInd),
                   Res
   			end,
  -			try
   			  case constrained_package_versions(DepGraph, Pkg, Constraints) of
   				[] ->
   				  {fail, [{Visited, Constraints}]};
  
positive.code:                 end,
                  ExistingConstraints0, [{SrcPkg, SrcVsn} | NewConstraints]).
  
  -spec is_version_within_constraint(vsn(),constraint()) -> boolean().
  is_version_within_constraint({missing}, _Pkg)->
      nope;
  is_version_within_constraint(_Vsn, Pkg) when is_atom(Pkg) orelse is_binary(Pkg) ->
      true;
  is_version_within_constraint(Vsn, {_Pkg, NVsn}) ->
  
negative.code: 				  {missing, Pkg};
  				Res ->
  				  lists_some(F, Res, PathInd)
  			  end.
  
  
  %% @doc This gathers the dependency constraints for a given package vsn from the
  