import std.stdio;

struct Wrapper(T) {
    @property T get() {
        return getter_();
    }

    ref Wrapper opAssign(T value) {
        setter_(value);
        return this;
    }

    ref Wrapper opOpAssign(string op : "+")(T value) {
        setter_(getter_() + value);
        return this;
    }

    ref Wrapper opOpAssign(string op : "-")(T value) {
        setter_(getter_() - value);
        return this;
    }

    ref Wrapper opOpAssign(string op : "*")(T value) {
        setter_(getter_() * value);
        return this;
    }

    ref Wrapper opOpAssign(string op : "/")(T value) {
        setter_(getter_() / value);
        return this;
    }

    T delegate() getter_;
    void delegate(T) setter_;

    alias get this;
}

struct Foo {
    @property Wrapper!int value() {
        return Wrapper!int(&getValue, &setValue);
    }

    @property Wrapper!int value(int value) {
        return Wrapper!int(&getValue, &setValue) = value;
    }

private:
    int value_;

    int getValue() const {
        return value_;
    }

    void setValue(int value) {
        value_ = value;
    }
}

int main(string[] args) {
    Foo foo;
    foo.value = 20;
    writeln(foo.value_);

    foo.value += 15;
    writeln(foo.value_);


    foo.value--;
    writeln(foo.value_);
    return 0;
}