Boost C++ Libraries

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Function template if_

Function template if_

boost::parser::if_

Synopsis

// In header: <boost/parser/parser.hpp>


template<typename Predicate> auto if_(Predicate pred);

Description

Returns an if_directive that fails if the given predicate pred is false, and otherwise, applies another parser. For instance, in if_(pred)[p], p is only applied if pred is true.