Why my map of pointer to function isn't compiling?

Question

I have this class :

class TaskManager
{
public:
  TaskManager();
  ~TaskManager();

  using taskFunction = void (TaskManager::*)(BabelPacket const &);
  void executeTask(Task const &task);
  void signInTask(BabelPacket const &);
  void signUpTask(BabelPacket const &);
  void signOutTask(BabelPacket const &);
  std::map<unsigned int, taskFunction> actions =
   {
     {BabelPacket::Code::SIGN_IN, &TaskManager::signInTask},
     {BabelPacket::Code::SIGN_UP, &TaskManager::signUpTask},
     {BabelPacket::Code::SIGN_OUT, &TaskManager::signOutTask},
  };
}

And this is my enum

struct      BabelPacket
{
  // Code enum
  enum struct   Code : unsigned int
  {
    NONE = 00,
    // Requests
    SIGN_IN = 100,
    SIGN_UP = 101,
    SIGN_OUT = 102,
  }
}

But when I compile this I got :

   includes/TaskManager.hpp:38: error: could not convert ‘{{SIGN_IN, &TaskManager::signInTask}, {SIGN_UP, &TaskManager::signUpTask}, {SIGN_OUT, &TaskManager::signOutTask}}’ from ‘<brace-enclosed initializer list>’ to ‘std::map<unsigned int, void (TaskManager::*)(const BabelPacket&)>’
       };
   ^

Got an idea why ?

Since you use `enum struct`, I don't think you can initialize the `unsigned int` key from enum members without casting them. — Fred Larson, Nov 01 '16 at 21:53

score 1 · Accepted Answer · answered Nov 01 '16 at 21:59

1

Since your enum is a class enum, it is not automatically convertible to int. Either make a regular enum out of it, our use static_cast, or use BabelPacket::Code as your map index type.

answered Nov 01 '16 at 21:59

SergeyA

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Why my map of pointer to function isn't compiling?

1 Answers1