Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
This is an older version of Boost and was released in 2018. The current version is 1.89.0.
BOOST_VMD_IS_TYPE — Tests whether a sequence is a VMD type.
// In header: <boost/vmd/is_type.hpp>
BOOST_VMD_IS_TYPE(sequence)sequence = a possible VMD type
returns = 1 if the sequence is a VMD type, 0 if it is not.
If the sequence is not a VMD data type this macro could lead to a preprocessor error. This is because the macro uses preprocessor concatenation to determine if the sequence is an identifier once it is determined that the sequence does not start with parentheses. If the data being concatenated would lead to an invalid preprocessor token the compiler can issue a preprocessor error.