Step 2 of 6

A factory registry

A factory creates objects by name (from a config file, a network message, a command line), returning them through a base-class pointer. Instead of a giant if/else chain, large codebases use a registry: a map from name to a creator function. New types register themselves without anyone editing the factory.

using Creator = std::function<std::unique_ptr<Weapon>()>;
std::map<std::string, Creator> creators_;

Returning std::unique_ptr makes ownership obvious: the caller owns the new object.

Your turn: implement Factory::add (returns false if the name is already registered), Factory::create (returns nullptr for unknown names) and Factory::names (sorted).

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