config_units.hpp

Go to the documentation of this file.

// SPDX-FileCopyrightText: 2026 CERN for the benefit of the SHiP Collaboration
//
// SPDX-License-Identifier: LGPL-3.0-or-later
 
// config_units.hpp — typed reads of dimensional configuration parameters
//
// Workflow configuration stays plain numbers (jsonnet has no unit syntax);
// the C++ parameter definition is the single source of truth for the unit.
// From the get_quantity() call onward the value is a typed quantity and can
// no longer be mixed up with a value in another unit.
 
#pragma once
 
#include <SHiP/Units.hpp>
#include <string>
 
#include "phlex/configuration.hpp"
 
namespace aegir {
 
template <auto U>
[[nodiscard]] mp_units::quantity<U, double> get_quantity(
    phlex::configuration const& config, std::string const& key,
    mp_units::quantity<U, double> fallback) {
  return config.get<double>(key, fallback.numerical_value_in(U)) * U;
}
 
}  // namespace aegir