Boost
C++ Libraries
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This version of Boost is under active development. You are currently in the develop branch. The current version is 1.90.0.
boost::parser::attribute
// In header: <boost/parser/parser.hpp> template<typename R, typename Parser> struct attribute { // types typedef unspecified initial_type; typedef unspecified type; };
A type trait that evaluates to the attribute type for parser Parser used to parse range R, as if by calling parse(r, parser), using some R r and Parser parser. Note that this implies that pointers to null-terminated strings are supported types for R. The result is not wrapped in a std::optional like the result of a call to parse() would be. If Parser produces no attribute, the result is the no-attribute sentinel type none.