range/algorithm/find_if.hpp

0001 //  Copyright Neil Groves 2009. Use, modification and
0002 //  distribution is subject to the Boost Software License, Version
0003 //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
0004 //  http://www.boost.org/LICENSE_1_0.txt)
0005 //
0006 //
0007 // For more information, see http://www.boost.org/libs/range/
0008 //
0009 #ifndef BOOST_RANGE_ALGORITHM_FIND_IF_HPP_INCLUDED
0010 #define BOOST_RANGE_ALGORITHM_FIND_IF_HPP_INCLUDED
0011
0012 #include <boost/concept_check.hpp>
0013 #include <boost/range/begin.hpp>
0014 #include <boost/range/end.hpp>
0015 #include <boost/range/concepts.hpp>
0016 #include <boost/range/detail/range_return.hpp>
0017 #include <algorithm>
0018
0019 namespace boost
0020 {
0021     namespace range
0022     {
0023
0024 /// \brief template function find_if
0025 ///
0026 /// range-based version of the find_if std algorithm
0027 ///
0028 /// \pre SinglePassRange is a model of the SinglePassRangeConcept
0029 /// \pre UnaryPredicate is a model of the UnaryPredicateConcept
0030 template< class SinglePassRange, class UnaryPredicate >
0031 inline BOOST_DEDUCED_TYPENAME disable_if<
0032     is_const<SinglePassRange>,
0033     BOOST_DEDUCED_TYPENAME range_iterator<SinglePassRange>::type
0034 >::type
0035 find_if( SinglePassRange& rng, UnaryPredicate pred )
0036 {
0037     BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange> ));
0038     return std::find_if(boost::begin(rng), boost::end(rng), pred);
0039 }
0040
0041 /// \overload
0042 template< class SinglePassRange, class UnaryPredicate >
0043 inline BOOST_DEDUCED_TYPENAME range_iterator<const SinglePassRange>::type
0044 find_if( const SinglePassRange& rng, UnaryPredicate pred )
0045 {
0046     BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange> ));
0047     return std::find_if(boost::begin(rng), boost::end(rng), pred);
0048 }
0049
0050 // range_return overloads
0051
0052 /// \overload
0053 template< range_return_value re, class SinglePassRange, class UnaryPredicate >
0054 inline BOOST_DEDUCED_TYPENAME disable_if<
0055     is_const<SinglePassRange>,
0056     BOOST_DEDUCED_TYPENAME range_return<SinglePassRange,re>::type
0057 >::type
0058 find_if( SinglePassRange& rng, UnaryPredicate pred )
0059 {
0060     BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange> ));
0061     return range_return<SinglePassRange,re>::
0062         pack(std::find_if(boost::begin(rng), boost::end(rng), pred),
0063              rng);
0064 }
0065
0066 /// \overload
0067 template< range_return_value re, class SinglePassRange, class UnaryPredicate >
0068 inline BOOST_DEDUCED_TYPENAME range_return<const SinglePassRange,re>::type
0069 find_if( const SinglePassRange& rng, UnaryPredicate pred )
0070 {
0071     BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange> ));
0072     return range_return<const SinglePassRange,re>::
0073         pack(std::find_if(boost::begin(rng), boost::end(rng), pred),
0074              rng);
0075 }
0076
0077     } // namespace range
0078     using range::find_if;
0079 } // namespace boost
0080
0081 #endif // include guard