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sasq64/callback.cpp

Last active April 5, 2021 14:27
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  1. sasq64 revised this gist Sep 21, 2016. 1 changed file with 39 additions and 39 deletions.
    78 changes: 39 additions & 39 deletions callback.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -5,51 +5,51 @@
    template<typename... X> struct Callback;
    template <typename R, typename ...ARGS> struct Callback<R(ARGS...)>
    {
    struct BaseFx
    {
    virtual R call(ARGS...) = 0;
    };
    struct BaseFx
    {
    virtual R call(ARGS...) = 0;
    };

    template <typename FX> struct Fx : public BaseFx
    {
    Fx(FX f) : f(f) {}
    virtual R call(ARGS... args)
    {
    return f(args...);
    };
    FX f;
    };
    template <typename FX> struct Fx : public BaseFx
    {
    Fx(FX f) : f(f) {}
    virtual R call(ARGS... args)
    {
    return f(args...);
    };
    FX f;
    };

    using Holder = std::shared_ptr<std::function<void(std::nullptr_t)>>;
    using Holder = std::shared_ptr<std::function<void(std::nullptr_t)>>;

    template <typename FX> Holder add(FX f)
    {
    callbacks.push_back(std::make_shared<Fx<FX>>(f));
    auto cb = callbacks.back();
    return Holder(nullptr, [=](std::nullptr_t) {
    callbacks.erase(remove(callbacks.begin(), callbacks.end(), cb));
    });
    };
    template <typename FX> Holder add(FX f)
    {
    callbacks.push_back(std::make_shared<Fx<FX>>(f));
    auto cb = callbacks.back();
    return Holder(nullptr, [=](std::nullptr_t) {
    callbacks.erase(remove(callbacks.begin(), callbacks.end(), cb));
    });
    };

    void call(ARGS... args)
    {
    for(auto &cb : callbacks)
    cb->call(args...);
    }
    void call(ARGS... args)
    {
    for(auto &cb : callbacks)
    cb->call(args...);
    }

    std::vector<std::shared_ptr<BaseFx>> callbacks;
    std::vector<std::shared_ptr<BaseFx>> callbacks;
    };

    int main()
    {
    // Outputs 5.0
    Callback<void(float, float)> test;
    {
    auto holder = test.add([](float x, float y) {
    printf("%.1f\n", x+y);
    });
    test.call(3.0f, 2.0f);
    }
    test.call(1.0f, 5.0f);
    return 0;
    }
    // Outputs 5.0
    Callback<void(float, float)> test;
    {
    auto holder = test.add([](float x, float y) {
    printf("%.1f\n", x+y);
    });
    test.call(3.0f, 2.0f);
    }
    test.call(1.0f, 5.0f);
    return 0;
    }
  2. sasq64 created this gist Sep 21, 2016.
    55 changes: 55 additions & 0 deletions callback.cpp
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,55 @@
    #include <functional>
    #include <vector>
    #include <memory>

    template<typename... X> struct Callback;
    template <typename R, typename ...ARGS> struct Callback<R(ARGS...)>
    {
    struct BaseFx
    {
    virtual R call(ARGS...) = 0;
    };

    template <typename FX> struct Fx : public BaseFx
    {
    Fx(FX f) : f(f) {}
    virtual R call(ARGS... args)
    {
    return f(args...);
    };
    FX f;
    };

    using Holder = std::shared_ptr<std::function<void(std::nullptr_t)>>;

    template <typename FX> Holder add(FX f)
    {
    callbacks.push_back(std::make_shared<Fx<FX>>(f));
    auto cb = callbacks.back();
    return Holder(nullptr, [=](std::nullptr_t) {
    callbacks.erase(remove(callbacks.begin(), callbacks.end(), cb));
    });
    };

    void call(ARGS... args)
    {
    for(auto &cb : callbacks)
    cb->call(args...);
    }

    std::vector<std::shared_ptr<BaseFx>> callbacks;
    };

    int main()
    {
    // Outputs 5.0
    Callback<void(float, float)> test;
    {
    auto holder = test.add([](float x, float y) {
    printf("%.1f\n", x+y);
    });
    test.call(3.0f, 2.0f);
    }
    test.call(1.0f, 5.0f);
    return 0;
    }