boost::algorithm::all — 'All' predicate
// In header: <boost/algorithm/string/predicate.hpp> template<typename RangeT, typename PredicateT> bool all(const RangeT & Input, PredicateT Pred);
This predicate holds it all its elements satisfy a given condition, represented by the predicate.
This function provides the strong exception-safety guarantee
Parameters:
Input
An input sequence
Pred
A predicate
Returns:
The result of the test