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Diffstat (limited to 'boost/metaparse/v1/cpp11/impl/string_at.hpp')
-rw-r--r-- | boost/metaparse/v1/cpp11/impl/string_at.hpp | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/boost/metaparse/v1/cpp11/impl/string_at.hpp b/boost/metaparse/v1/cpp11/impl/string_at.hpp new file mode 100644 index 0000000000..6540d56f65 --- /dev/null +++ b/boost/metaparse/v1/cpp11/impl/string_at.hpp @@ -0,0 +1,41 @@ +#ifndef BOOST_METAPARSE_V1_CPP11_IMPL_STRING_AT_HPP +#define BOOST_METAPARSE_V1_CPP11_IMPL_STRING_AT_HPP + +// Copyright Abel Sinkovics (abel@sinkovics.hu) 2016. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +#include <boost/metaparse/v1/impl/no_char.hpp> + +#include <boost/metaparse/limit_string_size.hpp> + +namespace boost +{ + namespace metaparse + { + namespace v1 + { + namespace impl + { + template <int MaxLen, int Len, class T> + constexpr int string_at(const T (&s)[Len], int n) + { + // "MaxLen + 1" adds the \0 character of the string literal to the + // limit + static_assert(Len <= MaxLen + 1, "String literal is too long."); + return n >= Len - 1 ? BOOST_NO_CHAR : s[n]; + } + } + } + } +} + +#ifdef BOOST_METAPARSE_V1_STRING_AT +# error BOOST_METAPARSE_V1_STRING_AT already defined +#endif +#define BOOST_METAPARSE_V1_STRING_AT \ + ::boost::metaparse::v1::impl::string_at<BOOST_METAPARSE_LIMIT_STRING_SIZE> + +#endif + |