src/gromacs/utility/arraysize.h

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  35 /*! \file
  36  * \brief
  37  * Provides asize() function for calculating the static size of an array at compile time.
  38  *
  39  * \inpublicapi
  40  * \ingroup module_utility
  41  */
  42 #ifndef GMX_UTILITY_ARRAYSIZE_H
  43 #define GMX_UTILITY_ARRAYSIZE_H
  44
  45 /*! \brief
  46  * Calculates the number of elements in a static array at compile time.
  47  *
  48  * \ingroup module_utility
  49  */
  50 template <typename T, int N>
  51 constexpr int asize(T(&/*unused*/)[N])
  52 {
  53     static_assert(N >= 0, "Do negative size arrays exist?");
  54     return N;
  55 }
  56
  57 #endif