TOOLS_PP is a small collection of preprocessor tools built on top of BOOST_PP (hence the name). It includes:
TOOLS_PP_ARRAY_CAT: concatenates two BOOST_PP arrays;
TOOLS_PP_ARRAY_LOWER_BOUND: finds the index of the lower bound of an item in a given array;
TOOLS_PP_ARRAY_SORT: sorts the given array;
TOOLS_PP_ARRAY_SORT_U: sorts the given array and remove duplicates.
All of them also have a _D variant that takes and uses the next available