TopKComp.h

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 *  Copyright 2018 Rice University                                           *
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#ifndef TOP_K_COMP
#define TOP_K_COMP

#include "AggregateComp.h"
#include "TopKQueue.h"
#include "LambdaCreationFunctions.h"

namespace pdb {

template <class InputClass, class Score, class ValueType>
class TopKComp : public AggregateComp<TopKQueue<Score, ValueType>, InputClass, int, TopKQueue<Score, ValueType>> {

public:

    Lambda<int> getKeyProjection(Handle<InputClass> aggMe) final {
        return makeLambda(aggMe, [&](Handle<InputClass>& aggMe) { return 1; });
    }

    Lambda<TopKQueue<Score, ValueType>> getValueProjection(Handle<InputClass> aggMe) override {
        return makeLambda(aggMe, [&](Handle<InputClass>& aggMe) {
            return TopKQueue<Score, ValueType>(1, Score(), ValueType());
        });
    }
};

}

#endif