text: 
  #ifndef BOOST_CONTRACT_DETAIL_ASSERT_HPP_
  #define BOOST_CONTRACT_DETAIL_ASSERT_HPP_
  
  // Copyright (C) 2008-2018 Lorenzo Caminiti
  // Distributed under the Boost Software License, Version 1.0 (see accompanying
  // file LICENSE_1_0.txt or a copy at http://www.boost.org/LICENSE_1_0.txt).
  // See: http://www.boost.org/doc/libs/release/libs/contract/doc/html/index.html
  
  #include <boost/contract/core/exception.hpp>
  #include <boost/contract/detail/noop.hpp>
  #include <boost/preprocessor/stringize.hpp>
  
  // In detail because used by both ASSERT and CHECK.
  // Use ternary operator `?:` and no trailing `;` here to allow `if(...) ASSERT(
  // ...); else ...` (won't compile if expands using an if statement instead even
  // if wrapped by {}, and else won't compile if expands trailing `;`).
  #define BOOST_CONTRACT_DETAIL_ASSERT(cond)                                     \
    /* no if-statement here */                                                   \
    ((cond) ? BOOST_CONTRACT_DETAIL_NOOP                                         \
            : throw boost::contract::assertion_failure(                          \
                  __FILE__, __LINE__, BOOST_PP_STRINGIZE(cond))) /* no ; here */
  
  #endif // #include guard
  