include/WeightBase.h

#ifndef HZZ2L2NU_INCLUDE_WEIGHTBASE_H_
#define HZZ2L2NU_INCLUDE_WEIGHTBASE_H_

#include <limits>
#include <string_view>

class WeightBase {
 public:
  virtual ~WeightBase() noexcept = default;

  virtual double NominalWeight() const = 0;

  virtual int NumVariations() const {
    return 0;
  };

  virtual double operator()() const {
    return NominalWeight();
  };

  virtual double RelWeight(int /*variation*/) const {
    return std::numeric_limits<double>::quiet_NaN();
  };

  virtual std::string_view VariationName(int /*variation*/) const {
    return "";
  };
};

#endif  // HZZ2L2NU_INCLUDE_WEIGHTBASE_H_

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