Rank (computer programming): Difference between revisions

Revision as of 20:27, 25 September 2016

Revision as of 06:34, 29 October 2017

Line 8:

<source lang="cpp">

#include <type_traits>

#include <cstddef>

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* it is an array; zero otherwise (which is the usual convention)

*/

template <typename tT> struct rank

{

{ static const std::size_t value = 0; };

};

template<typename tT, std::size_t nN>

struct rank<tT[nN]>

{

{ static const std::size_t value = 1 + rank<tT>::value; };

};

template <typename t, std::size_t nT>

constexpr auto rank_v = rank<T>::value;

/* Rank of an expression

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* Let the rank of an expression be the rank of its type

*/

template <typename t, std::size_t n>

template <typename T>

char(&rankof(t(&)[n]))[n];

using unqualified_t = std::remove_cv_t<std::remove_reference_t<T>>;

template <typename T>

auto rankof(T&& expr)

{

return rank_v<unqualified_t<T>>;

}

</source>

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:<source lang="cpp">rank<T>::value</source>

or the shorter form

and the rank of an array-expression ''expr'' by

:<source lang="cpp">rank_v<T></source>

andCalculating the rank of an array-expression ''expr''can bybe done using

:<source lang="cpp">sizeof(rankof(expr))</source>

==See also==