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 version of Boost is under active development. You are currently in the develop branch. The current version is 1.90.0.
boost::parser::eps_parser
// In header: <boost/parser/parser_fwd.hpp> template<typename Predicate> struct eps_parser { };
Matches anything, and consumes no input. If Predicate is anything other than detail::nope (which it is by default), and pred_(ctx) evaluates to false, where ctx is the parser context, the parse fails.